Compared to other services that might offer lower-quality leads or require higher upfront costs/paywalls, Prime Tracers also give you free lead credits on sign up so you can actually see the results before you commit to a purchase.

The standard rule is $250k per person who legally owns/occupies for the 2/5 year requirement. 

People don't read STR descriptions you see this alot with international properties where people expect US standards.

Forget the course and put that money on a quality vacation short-term rental.  

Perhaps a better vetting of the buyers on the BP side will enable better quality leads?

I've walked their properties in-person, and their build quality is good.

Best way to understand this is research appraisal standards and means. 

Cost per lead (CPL) is crucial—it shows how much you're paying to get a potential seller or buyer’s info, and you want this as low as possible without sacrificing quality.

The mailers I receive for my properties are not of a high enough quality, to make me believe the sender understands what gets a recipient to even open or read the mailer, let alone respond. 

Don't invest in a market if you can't find a quality PM!