How a solo developer cloned a SaaS and reached $20K/month

Executive overview

Most founders waste time hunting for original ideas. Proven demand already exists — listed publicly on business marketplaces for anyone to find.

Adrian Horning found a scraping API for sale on Acquire.com, reverse-engineered it, and rebuilt it himself. Within months he reached $20K/month with 80% margins.

Copy the validated concept, execute better, and ship fast — the idea doesn't need to be original.

The copying playbook

1. Visit the MicroAcquire/Acquire.com marketplace
2. Filter by SaaS, then set minimum asking price to $300K (or filter by ARR) — confirms real revenue
3. Pick a market where you have relevant skills or knowledge
4. Find the actual website: Google keywords from the listing title, or look for "competitor + alternatives" pages
5. Reverse-engineer customer acquisition — read everything, find the founder on Twitter/LinkedIn/podcasts
6. Build the product; don't copy word-for-word, copy the concept
7. Do something every day to promote or improve it — don't switch to another project

What Adrian built

• Scrape Creators: a credit-based social media scraping API (Instagram, YouTube, Twitter, Facebook/LinkedIn ad libraries)
• Handles proxy rotation, infrastructure, and reliability so developers don't have to
• Pay-as-you-go pricing: $10 / 5K credits, $50 / 25K credits, $500 / 500K credits
• ~600 total paying users; ~12 accounts drive the majority of MRR

How he grew it

• First customer came from posting a scraping demo on Twitter — the target company's CTO replied
• Offers 10K free credits in comments on any launch post related to scraping or social media
• High reliability and direct founder access differentiate it from competing scrapers

Tech stack and economics

• Node.js / JavaScript throughout; HTTP requests via the impit package (by Apify)
• Proxies: Evomi, Core Residential, Decodo, Webshare, Massive
• Hosting: Render.com + AWS Lambda; database: Supabase; front end: Astro + React; IDE: Cursor
• Monthly costs: ~$1,500 proxies, $500 overnight monitoring (Philippines contractor), $400 servers
• Gross margin: ~80%