Pay someone. Put an ad on CL gigs. Start with your state, or a large target state. Start with a small sample, refine your technique. I’ve done this sort of

Pay someone. Put an ad on CL gigs. Start with your state, or a large target state. Start with a small sample, refine your technique. I’ve done this sort of thing (other niche industries) by web scraping. Ask for a csv, with specific fields (name, address, phone, email, number of employees or other size metrics*)