Agree 100%. For trades I also add a photo of every finished job with a short caption. Profile views went up noticeably for a roofer client once we started doing that consistently.
Also search site:domain.com “write for us” or “sponsored post”. If they have a big public price list, every SEO seller on the planet is already using them.
Half live is pretty normal for a domain that dropped 3-4 years ago. I’d only count the live ones with actual traffic when you decide on a price.
On your second question: I rebuild the top 5-10 pages that had links pointing to them (same URL, updated content) and put everything else new. Keeping the URLs that have links does more than any redirect trick.
