1. Verdict
Definition of "success"
This portfolio uses an MRR ladder ($1k → $50k by month 24, profitable at that level) plus two fixed tiers so ideas can be compared (see ../../README.md):
- Tier A (venture): $1M ARR within 36 months, ≥70% gross margin, ≥50% month-12 logo retention.
- Tier B (profitable business, the default target): $20k+ MRR within 24 months, profitable, ≥80% gross margin, ≥70% month-3 retention.
Probability: five versions of the idea
Judgment estimates of reaching each MRR level by month 24. Each cell shows ~15 hrs/week / full-time, with the founder conditions in WHAT-TO-DO-AND-AVOID.md met.
| Version | $1k | $5k | $10k | $20k | Why |
|---|---|---|---|---|---|
| As described: a big, popular source head-on (HubSpot, Jira, Shopify) | 25% / 35% | 6% / 10% | 3% / 5% | 1% / 2% | HubSpot and Jira have native Sheets add-ons with 129K+ and 3.43M+ installs. Shopify has 15+ add-ons, including SyncWith and Adveronix. |
| ClickUp, two-way (a #2 behind ClickUp to Sheets) | 35% / 50% | 10% / 17% | 4% / 8% | 1% / 3% | Demand is proven (756 votes on ClickUp's own request board, 29K+ installs for the incumbent), but the incumbent is rated 4.7, two-way, and updated in Jul 2026. |
| Stripe, finance reporting in Sheets | 30% / 45% | 8% / 14% | 3% / 6% | 1% / 2% | Buyers pay, and there's no strong dedicated add-on. But demand looks thin: the top dedicated Stripe add-on has 234 installs, and Baremetrics' own has 444. Horizontal connectors already cover Stripe. |
| A multi-source "connect anything" connector | 15% / 25% | 3% / 6% | 1% / 3% | <1% / 1% | Coefficient (654K+), Coupler.io (440K+), Unito (477K+) and API Connector (11M+) own it. |
| Recommended: Airtable ↔ Sheets, two-way, quota-aware | 45% / 60% | 15% / 25% | 6% / 11% | 2% / 4% | No native sync, a weak dedicated incumbent, team buyers who already pay $20–45 a seat, and two-way as the edge. Capped by pool size. |
The recommended version at the $3k and $50k levels: 25% / 38% and <0.5% / 1%.
Base rate: no verified base rate. Google publishes no add-on revenue data, and no survey of add-on outcomes was found. The anchors are Sync2Sheets ($9k MRR after 3 years, flat for the following year) and BudgetSheet ($83/mo in early 2021, then $5k/mo in Dec 2024, built part-time). Both are founder-reported. See 10.
Portfolio tiers
| Tier | ~15 hrs/week | Full-time | Why |
|---|---|---|---|
| Tier A ($1M ARR / 36 months) | <0.5% | <0.5% | That's ~2,600 customers at $32. No single-source Sheets add-on is known to be near that. |
| Tier B ($20k+ MRR / 24 months, profitable) | ~2% | ~3% | ~620 paying teams, and the Airtable-to-Sheets pool may not hold that many buyers. Margin and month-3 retention would pass. |
Fundable in current form?
No. It isn't meant to be. A single-source sync add-on is a small, high-margin, owner-run business. Its natural exit is a sale at a multiple of profit, not a venture round. See 06.
One-paragraph verdict
The pattern is real. A solo developer can build a Sheets sync add-on in weeks, list it for free, and get paying customers from Marketplace search with no ad spend. Sync2Sheets and BudgetSheet prove that. But the idea as catalogued leaves the only decision that matters, which source, open, and the obvious picks are already taken:
- Native sync: Jira, HubSpot, Linear and Asana.
- Strong incumbents: Notion and ClickUp.
- Horizontal connectors cover everything one-way.
Airtable is the one popular, paying, API-friendly source without a native sync or a good dedicated add-on. Two-way sync that respects Airtable's API cap is a real edge. Build that, charge from day one on a trial, and expect a durable $3–5k MRR business, not a $20k one. Getting beyond ~$10k almost certainly means a second source on the same engine, and that belongs after month 18, not before.