However, my agent did get the listing agent on the phone once (while theyvwere moving out of town) and learned that the owner was a dentist who "didn't realize it'd be this much work" and many other negative factors.

Be apart of RE groups/run one, become a thought leader (blogs, youtube channel, podcast of your own or go on others, linked in, facebook, etc), Join non-profits and become a leader, get in with a group of successful professionals (Doctors, Lawyers, Dentists, Athletes, etc) and add value to their profession, team up with other syndication companies and talk about what you are doing with everyone that you know. 

I have super-duper limited knowledge around this but if you have a tenant like a dentist that has spend huge amounts of money building out their space you have a lot more stability than something like a barber shop. 

My Father is completely debt-free and makes 200k a year in California as a Dentist.

But I honestly think a better comparison would be a doctor and a CPA, almost any kind of engineer, a lawyer, and a dentist.

Doctors, Dentists, lawyers, etc, all can refer people to you and you can refer people to them in return. 

Hello Bigger Pockets Network,I am a 28 year old dentist who runs a private practice in Milwaukee WI. 

I am a dentist and I can only do real state part time.

This prospective office has a dentist occupying 1/3rd, with the remaining space all being very small (100 sq ft to 250 sq ft) offices with short term leases (no more than 12 months).

If they are close, I error towards buying the rate down now, since no one can guarantee where rates will be in six months AND convenience of doing it all at once... unless my winning personality is just so great that you enjoy the mortgage process so much that you want to do it twice... sometimes I feel like a dentist!