The clearest lesson from early freelance gigs: if scope isn't written, it doesn't exist. "Small tweak" can be the most expensive phrase.
I accept when deliverable is clear, repo exists, timeline is one to two weeks, and there's a single decision-maker. I decline vague QA, 24/7 availability, and "small jobs" spanning five modules.
Fixed-price puts risk on you. Add buffer (20-30%) or propose T&M. Scope creep is managed by contract, not chat.
Reviews are secondary; repeat clients and references are primary. The first gig is about relationship, not portfolio padding.