Pebble Rock Capital

The Compounding Loop

Trading Book +$312 profit generated · 14 trades

→

Portfolio +38.4% return since inception · 9 positions

Total Capital Deployed

$847

Blended Return

+41.2%

TB Trades This Month

4

TB Win Rate

86%

Capital Recycled → PF

$200

Portfolio Write-offs

1 (NFT)

Recent Activity

Trade

Vintage Levi's 501 — Thrift → eBay

Feb 20, 2026 · Thrift / Denim · 6 days held

+$28 · +467%

Memo

LEGO Millennium Falcon #10179 — Q1 Update

Feb 18, 2026 · Portfolio · Thesis intact, +109.8%

+$335

Trade

Game Boy Color + 3 games — Facebook → eBay

Feb 14, 2026 · Retro Gaming · 11 days held

+$46 · +164%

Collection

Added: Braun T3 Pocket Radio (Rams, 1958)

Feb 10, 2026 · Vintage Tech · Not for sale

♦ Keep

Memo

Q1 2026 LP Letter: The LEGO Thesis Vindicated

Feb 1, 2026 · Quarterly Letter · Fund Overview

Est. 6 min

Trade

Casio F-91W (NOS, original box) — eBay arbitrage

Jan 28, 2026 · Watches · 3 days held

+$14 · +175%

Full Trade Log → Full Portfolio →

The Trading Book — Active Arbitrage Log

Every flip, logged in full. Thrift, eBay, private markets. The Trading Book is the compounding engine — it generates the capital that the Portfolio deploys. Margins are published. Mistakes are included.

Trades Completed

14

Win Rate

86%

Avg Gross Margin

+44%

Avg Hold (Days)

8.2

Total Profit

+$312.40

→ Deployed to PF

$200.00

Trade Log — All Closed Positions · Q1 2026
Item	Source	Buy	Sell	Days	Gross $	Gross %	Note
Levi's 501 (vintage, W32)1990s, thrift find	Thrift	$6	$34	6	+$28	+467%	—
Game Boy Color + 3 gamesPurple GBC, Pokémon Gold/Silver	FB Mkt	$28	$74	11	+$46	+164%	Note →
Casio F-91W (NOS, orig. box)Unused, full packaging	eBay	$8	$22	3	+$14	+175%	—
Penguin Classics lot (×12)Vintage 60s–70s editions	Thrift	$4	$31	14	+$27	+675%	—
Sony Walkman WM-2Working, original case	Estate	$15	$58	9	+$43	+287%	Note →
Vintage denim jacket (Lee, M)1980s, minor wear	Thrift	$12	$55	8	+$43	+258%	—
Kodak Instamatic 100 (boxed)Complete, unused film included	Thrift	$3	$19	5	+$16	+433%	—
Hot Wheels Redline lot (×8)1968–70, mixed condition	Thrift	$6	$44	12	+$38	+533%	—
Vintage Pyrex mixing bowl setPrimary colours, 4pc, 1960s	Thrift	$8	$9	22	+$1	+13%	—
Supreme Box Logo Tee (SS18)White, L, worn once	eBay	$60	$38	31	-$22	-37%	Note →

Recent Trade Notes

Trade Note

Game Boy Color Lot — Why Bundling Changes Everything

Feb 14, 2026 · Retro Gaming · +$46 · +164%

The sourcing insight here wasn't the Game Boy — it was the games. The seller listed "GBC + games" as a single lot on Facebook, priced for the hardware. Individual sold listings on eBay showed Pokémon Gold alone trading at $28–32 CIB. We paid $28 for the bundle. The games were the margin.

Trade Note

Supreme SS18 Box Logo — A Lesson in Category Liquidity L

Jan 12, 2026 · Streetwear · -$22 · -37% · Loss

We bought this at what appeared to be a discount to StockX comps. We were wrong about the category. Supreme resale has compressed significantly since 2021. The buyer pool for a worn large at this price point is thin. We held 31 days and cut at a loss. Note for future: check sell-through rate, not just last-sale price.

The Portfolio — Long-Term Thesis Holds

Conviction positions in structurally scarce alternative assets. Every position has a written Investment Memo filed before purchase. Hold periods are measured in months and years. Several positions were funded by Trading Book profits — those are marked.

Active Positions · Q1 2026
Asset	Cat.	Cost	TB Funded	Mkt Val.	Return	Status
LEGO #10179 (sealed)Millennium Falcon, 2007	LEGO	$305	TB $200	$640	+109.8%	Hold
Pokémon Charizard 1st Ed.PSA 7, 1999 Base Set	TCG	$285	—	$320	+12.3%	Hold
Yeezy 350 V2 "Zebra"DS, Size 10, 2022	SNKR	$140	—	$180	+28.6%	Hold
Basquiat "Eyes & Eggs"Offset litho, signed ed., 1983	ART	$180	—	$220	+22.2%	Hold
WoW Collector's Ed.Sealed, Blizzard 2004	GAME	$30	—	$85	+183.3%	Hold
Iron Maiden — Killers LP1st UK Press, VG+/NM, 1981	VINYL	$43	—	$62	+44.2%	Hold
Macallan 12yr 2019Single Malt, 750ml, sealed	WHSK	$90	—	$95	+5.6%	Monitor
Birkenstock Boston ShearlingDS, Tan, Size 41, 2021	FWEAR	$120	—	$155	+29.2%	Hold
mfer NFT #4421Ethereum, sartoshi, 2021	NFT	$165	—	$48	-71.2%	Write-off

Latest Investment Memos

New Position

LEGO Millennium Falcon #10179 — A Scarcity Play in the Secondary Brick Market NEW

Feb 18, 2026 · Hard Assets · Est. 4 min · Funded by Trading Book ($200)

Thesis: The #10179 represents a canonical convergence of IP moat, structural supply constraint, and generational nostalgia premium. Acquired at $305, 15% below BrickLink comps of ~$355–370 sealed. 18-month target: $450–520.

LEGOScarcityTB Funded

Thesis Note

Why Sealed Vintage Video Games Are the Art Market of the 2030s

Jan 14, 2026 · Macro / Thesis · Est. 7 min

The WoW Collector's Edition was acquired at $30 and now trades at $85. The thesis is structural: sealed vintage games are a convergence of nostalgia, provenance, and grading infrastructure that is creating institutional legitimacy from the bottom up.

Video GamesMacroLong-Term

The Collection

Objects kept for their own sake — not tracked for return, not available for sale, not fund assets. The Collection is what's left when you remove the P&L entirely: things acquired for their craft, their cultural significance, or simply because they're too good to let go. Some inform how we think about markets. Most are just here because they should be.

Not fund assets · Not for sale · Returns not tracked

Vintage & Retro Tech

Not For Sale Vintage Tech · 1958

Braun T3 Pocket Radio

Dieter Rams, Braun AG — West Germany, 1958

The T3 is why we care about objects at all. Rams designed it the same year he wrote the ten principles of good design and it satisfies every one of them. Technically it's a radio. Practically it's a proof that the right constraints produce better work than no constraints.

Not For Sale Vintage Tech · 1984

Apple Macintosh 128K

Apple Computer Inc., Cupertino — original 128K, working

Still boots. The happy-face startup screen has not gotten old. This one came from an estate sale in 2021 and had been used continuously until the mid-1990s — you can tell by the keyboard wear. Paid $180. Appraised at considerably more. Irrelevant.

Not For Sale Vintage Tech · 1979

Sony Walkman TPS-L2

First generation, original case and headphones — Japan, 1979

The original. Not the WM-2, not a reissue — the actual first Walkman, with the two headphone jacks for sharing. The orange foam headphones are somehow still intact. This is the object that changed how people relate to music in public space, and it fits in a jacket pocket.

Not For Sale Retro Computing · 1977

HP-35 Scientific Calculator

Hewlett-Packard, 1972 — first scientific pocket calculator

HP called it "a miracle" in their 1972 press release and they were not wrong. RPN entry, red LED display, and it made the slide rule obsolete in about eighteen months. This one was an engineer's daily tool for a decade — the case shows it.

Art & Prints

Not For Sale Art Print · 1966

Penguin Books — "The Trial" (Kafka)

Penguin Modern Classics, 1966 — Romek Marber cover design

Marber's grid system for Penguin in the 1960s is one of the best examples of a design system actually working across a large catalogue. This copy is unread and in near-perfect condition. Framed. The typography alone justifies the wall space.

Not For Sale Concert Poster · 1968

Fillmore West — Grateful Dead (BG-105)

Bill Graham presents, Wes Wilson design — San Francisco, 1968

Wilson's psychedelic lettering is almost unreadable, which was the point — you had to stop and look. BG-105 is one of the more understated pieces from the Fillmore run. Found it at an estate sale in 2022, rolled in a tube, unframed. Now framed.

Toys, Figures & Collectibles

Not For Sale Action Figure · 1977

Star Wars Early Bird Certificate Package

Kenner, 1977 — the "empty box" Christmas, complete with mailer

Kenner couldn't manufacture the figures in time for Christmas 1977, so they sold a certificate promising four figures to be mailed in 1978. This is the complete package — the certificate, the display stand, the cardboard figures, and the mailer. It's essentially a receipt for toys that hadn't been made yet.

Not For Sale Toy · 1998

Original Furby (Tiger Electronics)

Tiger Electronics, 1998 — first edition, grey/white, working

This one still works, which is alarming. It's here partly because it's a genuinely interesting object — the first mass-market toy with a learning algorithm — and partly because it's impossible to sell a working Furby without feeling like you're doing something wrong.

Books & Media

Not For Sale Book · 1965

Situationist International Anthology (1st ed.)

Bureau of Public Secrets, 1981 — Ken Knabb translation, signed

The SI's theory of the spectacle is more accurate now than when it was written in 1967, which is not a comfortable thing to conclude. The Knabb translation is the standard one. This copy is signed by Knabb at a reading in San Francisco in 2004, which is the kind of thing that becomes meaningful over time.

Not For Sale Vinyl · 1973

Pink Floyd — The Dark Side of the Moon

Harvest Records, UK 1st press (SHVL 804) — NM/NM

Not in the Portfolio because it was never going to be sold. The UK first press has a quality to it that later pressings don't replicate — the lacquer work is audibly different. This was acquired before we understood what we were looking at, which is sometimes the best way to acquire things.

The Framework

The Compounding Loop

Source → Flip → Compound → Deploy

The Trading Book runs continuously. We source underpriced goods across thrift stores, eBay, and private markets — price them correctly, sell at a margin, reinvest. When enough capital accumulates, we evaluate whether a Portfolio thesis position has earned an allocation. Trading Book profits fund the entry. The flip becomes the investment.

Trading Book Framework

Sourcing

We look for systematic mispricings, not lucky finds

Sellers who don't know what they have. Items in the wrong category. Goods priced for local demand when national demand is meaningfully higher. We operate in used goods, vintage items, and eBay arbitrage. Minimum target: 30% gross margin before fees. We model net margin, not gross — platform fees run 13–15%.

Rules

No position held longer than 60 days without a reprice. No buying items we can't verify. No chasing trending categories — we prefer thin, consistent markets over hot, crowded ones. Every trade is logged with source, buy price, sell price, platform, days held, and margin. Losses are published.

Portfolio Framework

Criteria

Four criteria, all required: Structural scarcity (supply fixed or declining), Cultural durability (demand anchored beyond current trend), Market inefficiency (priced below rational value vs. comparable sales), Verifiable provenance (authenticity confirmable through certification or inspection). No memo, no buy.

Hold Philosophy

We hold until the thesis is fully expressed or the thesis is broken. We do not exit because the price declined. We do not run stop-losses on thesis positions. A stop-loss on a sealed LEGO set is a category error. Either the scarcity thesis is intact or it isn't.

The Collection

The Collection is a third relationship to physical objects — kept for their own sake, not tracked for return. It exists separately from both books. Objects in the Collection sometimes inform how we think about markets. Most are just here because they're too good to let go. Nothing in the Collection is a fund asset and none of it is for sale.

About the Fund

A capital compounding experiment in physical goods markets.

Pebble Rock Capital is a single-operator fund running two books — an active Trading Book in used goods and eBay arbitrage, and a Portfolio of long-term thesis holds in structurally scarce assets. Total AUM is under $1,000. Everything is published in real time.

The Question

Can you compound capital from nearly nothing, in physical goods markets, with full public transparency?

That's the experiment. This site is the record of how it goes. We started with the observation that alternative asset markets contain persistent pricing inefficiencies that institutional capital ignores — they're too small, too fragmented, too illiquid. That's the opportunity. We also have a collection of things we'd never sell, which turns out to be the context that makes the rest of it make sense.

Why Public

Transparency is a methodology, not a marketing choice. Public documentation forces better thinking, better pricing, and a higher standard for the work. We're also not aware of anyone else running both books simultaneously and publishing the full operational record in real time. If the experiment produces anything useful — a framework, a set of sourcing patterns, an honest record of what works — it's more useful public than private.

The Name

BlackRock, Oaktree, Greylock, Granite Point — the institutional naming convention is geological permanence. We buy used goods at thrift stores, track a sealed LEGO set as a thesis position, and keep a working 1958 transistor radio because Dieter Rams designed it. Pebble Rock is an honest name for what we are: same geology, considerably smaller scale.

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Disclosures

Not investment advice. Not a fund you can invest in. One LP: me. AUM under $1,000. Not registered with the SEC or any other body. Past performance of sealed LEGO sets does not guarantee future results. The mfer NFT position was a mistake and we've written a Trade Note about it so it doesn't happen again.