Campus textbook resale
Sample team · Venture Workshop · 2026-10-27 · Part A · standard tier
The call Build (dry run)
Dry run: 1 deep pain by the code rule; a live run writes the real insight.
Confidence: low. What would change this call: Dry run placeholder.
Value proposition
We help CUNY students who buy required textbooks every semester with: textbooks cost cuny students hundreds of dollars a semester and the bookstore buys them back for almost nothing.
Gauges
Pain and Reach both need 7 or more for a confident call.
Pain 7/10
Rule: 3 + 2 per deep pain (1) + up to 2 for action or money rows (6). (Sharpen interview score: 7/10.)
Sources: Perlego: Books & Textbooks · 1★ review: Impossible to cancel… · Perlego: Books & Textbooks · 1★ review: Worst App for the money · r/CUNY post: Anyone need free textbooks?
Reach 8/10
Copied from the Sharpen interview in a dry run. (Sharpen interview score: 8/10.)
Edge 4/10
Copied from the Sharpen interview in a dry run. (Sharpen interview score: 4/10.)
Evidence
| Claim | Supports | Rung | Source |
|---|---|---|---|
| Competition | |||
| Bookshelf is one of the closest apps on the App Store. | context | market | Bookshelf |
| Perlego: Books & Textbooks is one of the closest apps on the App Store. | context | market | Perlego: Books & Textbooks |
| Get Textbooks: Compare Prices is one of the closest apps on the App Store. | context | market | Get Textbooks: Compare Prices |
| Audience | |||
| A quote from a deep pain cluster (dry-run keyword rule). | pain | money | Perlego: Books & Textbooks · 1★ review: Impossible to cancel… |
| A quote from a deep pain cluster (dry-run keyword rule). | pain | talk | Perlego: Books & Textbooks · 1★ review: Worst App for the money |
| A quote from a deep pain cluster (dry-run keyword rule). | pain | talk | r/CUNY post: Anyone need free textbooks? |
| Pricing | |||
| Mentions paying, subscribing, or upgrading (dry-run keyword rule). | pain | money | Bookshelf · 1★ review: Videos |
| Mentions paying, subscribing, or upgrading (dry-run keyword rule). | pain | money | Perlego: Books & Textbooks · 1★ review: Double Subscription!! |
Three next moves (this week)
- Price it and quote the next five. Put a price on the first version and quote it to five CUNY students who buy required textbooks every semester. The ask: A yes or no at a named price.
- Take deposits, not interest. Put a small refundable deposit behind the sign-up button on a one-page site. The ask: A refundable deposit.
- Set a threshold before building. Decide how many paid commitments justify building, and refund everyone if you miss it. The ask: A pre-order.
Part review
| Part | Rating | Comment | Suggested rewrite |
|---|---|---|---|
| Who | ok | Dry run: not reviewed. | — |
| Pain | ok | Dry run: not reviewed. | — |
| Solution | ok | Dry run: not reviewed. | — |
Only weak parts get a rewrite. The founder's original wording above is kept either way.
Devil's advocate: the case for Park
Dry run placeholder. A live run argues the strongest case against "We help CUNY students who buy required textbooks every semester with: textbooks cost cuny students hundreds of dollars a semester and the bookstore buys them back for almost nothing." from the interview.
- Placeholder: is the pain frequent enough to change behavior?
- Placeholder: will people pay, or only agree it's annoying?
- Placeholder: can a free incumbent copy this quickly?
What would change the advocate's mind: Placeholder: deposits or pre-orders from strangers.
Stage 2 · Pain map
Sources read: 25 Reddit posts and comments, 0 cited web quotes, 16 Hacker News comments, 36 low-star App Store reviews. 42 became evidence rows.
Deep Mentions of "textbook"
Dry run: 20 rows grouped by keyword, not by meaning. (20 rows from 8 distinct sources; action or money signal: yes)
“Impossible to cancel subscription. There website constantly crashes and there’s no option in the app to cancel it. Awful company”
“Worst App for the money. Just not worth the money and the product is of zero value. Never again.”
“Anyone need free textbooks?. Giving away free, in little Haiti. Used, but decent condition. 1) Precalculus, A Right Triangle Approach, 3rd edition. By Ratti & McWaters. link for reference …”
Shallow Mentions of "used"
Dry run: 12 rows grouped by keyword, not by meaning. (12 rows from 1 distinct source; action or money signal: yes)
“Update made it impossible to use the app. The new update requires iOS 26 which my phone cannot do. This makes it impossible to use the app now with an…”
“CAPTCHA. For some reason Thriftbooks has decided to increase their security and now I have to do a CAPTCHA every time I open the app. I don’t know if there…”
“Doesn’t load. This app doesn’t load I’ve deleted and reinstalled”
Shallow Mentions of "bookshelf"
Dry run: 10 rows grouped by keyword, not by meaning. (10 rows from 1 distinct source; action or money signal: no)
“Read Aloud Feature. The voices in English are so robotic. It’s annoying to listen to. I’ve adjusted the speed and it’s even worse.”
“Audio. The audio option is terrible. You can barely understand what is being said. I even tried changing the settings and the different voices and none of them helped. Just…”
“Too many app crashes. I can’t keep up with lecture or reading when apps always closing on its own when jumping to another chapter.”
Where they gather: r/CUNY · r/college · r/textbook · Hacker News · Bookshelf reviews · Perlego: Books & Textbooks reviews · ThriftBooks: New & Used Books reviews
Trigger moments:
- But when I did that, everybody working on the Internet could meet in one large classroom.
- I can’t keep up with lecture or reading when apps always closing on its own when jumping to another chapter.
- I can’t access the table of contents or anything on the toolbar when attempting to read a book.
- For some reason Thriftbooks has decided to increase their security and now I have to do a CAPTCHA every time I open the app.
Stage 3 · Market scan
This table was written by rules from App Store and YC data, not by the model.
| App or company | Rating | Ratings | Price | Launched | Updated | Positioning | Biggest gap |
|---|---|---|---|---|---|---|---|
| Bookshelf | 4.7 | 80,287 | Free | With Bookshelf, you can enjoy a digital-first, comprehensive study experience from the convenience of your iPad or iPhone. | Low-star reviews: "Read Aloud Feature", "Audio", "Too many app crashes" | ||
| Perlego: Books & Textbooks | 4.5 | 1,138 | Free | Access a wide range of academic textbooks and books with Perlego — the digital library that helps students, researchers, and lifelong learners study on their ow | Low-star reviews: "Double Subscription!!", "Disappointed", "Impossible to cancel subscription" | ||
| Get Textbooks: Compare Prices | 5.0 | 3 | Free | Find the cheapest copy of any textbook in seconds. | No low-star reviews collected. | ||
| ThriftBooks: New & Used Books | 3.8 | 1,575 | Free | Shop 13 million new and used books at up to 90% off list price. | Low-star reviews: "Doesn’t load", "Login", "ThriftBooks" | ||
| EDUBOOKS | 4.2 | 36 | Free | Save 90% on textbooks! | No low-star reviews collected. | ||
| RedShelf | 4.5 | 7,079 | Free | The RedShelf eReader companion app provides access to read and engage with your textbooks located in your RedShelf account on the My Shelf page. | No low-star reviews collected. |
White space: Not assessed by rules. A model write-up compares what each competitor leaves unserved.
Market size (bottom-up):
- TAM: Not estimated by rules.
- SAM: Not estimated by rules.
- SOM: Not estimated by rules.
Risk flags:
- Dominant incumbent. Bookshelf has 80,287 ratings. (source)
How this was scored
Dry run: scores come from fixed rules, not a model. Pain uses the deep-pain rule; Reach and Edge are copied from the interview.
- Gauges use the CEO Signal rubric: Pain and Reach must both reach 7 for a confident call.
- Evidence is graded talk → action → money. A pain counts as deep only with 2+ distinct sources and at least one action or money signal.
- Every quote was checked against its source text, and every claim links to a page returned by a real search or data tool during this run. Anything that failed either check was dropped.
Search interest, for context only (not scored): textbook · textbooks
Run notes
- Paid web search skipped in this dry run (a live run would use up to 2 searches).
- Dry run: the competitor table was written by rules from App Store and YC data.
- Screenshot teardown is off on the standard tier. Add --teardown to include it.
Sharpen interview
- Coach: Where could you message ten of these people this week, and how many are there?
Founder: Every class group chat has people asking who has last semester's book, and those chats have 50 to 200 students each. - Coach: What happens the day this goes wrong, and what do people do instead today?
Founder: I'm not sure yet. - Coach: What happens the day this goes wrong, and what do people do instead today?
Founder: I'm not sure yet. - Coach: Where could you message ten of these people this week, and how many are there?
Founder: Two friends sold books on Facebook Marketplace but got ghosted at meetups. - Coach: What can you put behind a test this month, in dollars and hours per week?
Founder: I spend about $400 a semester on textbooks, and the bookstore paid me $12 total for three books at buyback.
Projected cost of a live run
Nothing was spent. Estimated lines measure the real prompts this run built (about 4 characters per token) and assume a typical reply length. Assumed lines cover paid web searches, whose size depends on what they find. Tavily searches are free and not listed.
| Stage | Model | Input tokens | Cache reads | Output tokens | Web searches | Cost | Basis |
|---|---|---|---|---|---|---|---|
| Sharpen | claude-haiku-5-5 | 13,404 | 0 | 5,400 | 0 | $0.004 | estimated |
| Sharpen (auto founder) | claude-haiku-5-5 | 2,128 | 0 | 1,200 | 0 | $0.001 | estimated |
| Devil's advocate | claude-haiku-5-5 | 515 | 0 | 900 | 0 | $0.001 | estimated |
| Dig (web search) | claude-sonnet-5-5 | 15,500 | 0 | 1,500 | 2 | $0.066 | assumed |
| Dig (extract) | claude-haiku-5-5 | 7,813 | 0 | 10,000 | 0 | $0.006 | estimated |
| Dig (cluster) | claude-haiku-5-5 | 2,889 | 0 | 2,000 | 0 | $0.001 | estimated |
| Scan (write-up) | claude-haiku-5-5 | 1,565 | 0 | 1,800 | 0 | $0.001 | estimated |
| Verdict | claude-sonnet-5-5 | 7,050 | 0 | 4,500 | 0 | $0.059 | estimated |
| Total | $0.139 |
Budget: $0.25. Within budget.
0 unsourced claim references were dropped.