Zero-dollar marketing is time spent where trust forms: a complete Google Business Profile (free, and for local search, decisive), the review ask on every completed job, personal referral requests to your best customers, and answering community questions where your trade comes up.
The free assets most skip: your own past customers (a reactivation text costs nothing), your vehicle and jobsite signage, partnerships with adjacent trades (the plumber and electrician who swap referrals both eat), and one genuinely useful page answering your market's biggest question.
The honest boundary: no-budget marketing buys customers with hours, and it caps out. Its real job is funding the transition. The first $500 of profit routed into search ads starts the engine that scales past your calendar.