What are the chances that someone would search this online forum, find this thread, and create an account just to make a positive comment on this thread about this company?

Find ways to consistently and systematically add more people to your database each week - i.e. cold calling, networking, online marketing4.

The majority of buyers appreciate the expertise that a good agent provides (local market knowledge that can only be gained by being active in the market buying and selling all the time, looking at most of the new listings in person or at least online daily, a background in or at least understanding of building construction, relationships within the network of professionals in the industry doing deals, vendor referrals, legal protection through E&O insurance and keeping up with constant changes in approved contracts and required disclosures and forms, negotiating skills (the average person is terrible at negotiating directly and has no desire to, I find Americans are uniquely averse to negotiating and prefer to outsource it but I digress), etc.).

You'll need good contact info for them to be able to collect, and ideally the new address for the tenant however which if you don't have can probably be found easily with some online sleuthing/ contacting their employer, skip tracing software, etc. 

Each town is a little different, some require you to do a landlord registration and/or will want to do an inspection before you put a tenant in (calling the town would probably be the easiest, or they may have the info right online).

You can also check their reviews online at Google, Facebook, or Yelp.

Then just yesterday, I come across the 1099 / 1099-NEC form requirements online from my own research.

A friend advised me to check reviews online and look for someone local with experience in single-family homes.

they look like they have a legitimate website but I'm not seeing them on here or any google reviews which is a little fishy (unless google is just not showing me for some reason)

Recommended resources include books, podcasts, websites, forums, and online courses.