To become a doctor, I will have to complete a 3-7 year residency, during which I am paid <$40,000/year. 

Doesn't really matter what the industry is, doctors, lawyers, engineers, accountants, police officers, firemen, teachers, they all receive formal training and are mentored by peers, well, more like superiors.  

When I started buying houses in the early 2000s, I had a doctored guru contract. 

You could check with them.I've heard that if someone is in your Profession then you can pay a referral fee: Doctors, Lawyers, RE Agents, etcbut if they're not, then you can hire them or pay advertising fees.

With uber insurers have been updating that exclusion and even charity drivers are being caught in the exclusion (driving a church member regularly to the doctor for no charge was deemed to be excluded in a GA court; State Farm litigated that one).

Your family, a friend, you doctor, your lawyer, your barber, your stock broker, your insurance agent......they may lend you the money but they are NOT in the business of lending money. 

In my lease the tenant has to have carpet professionally cleaned when they leave and provide a receipt (no Rug Doctors).

One was rented to a doctor & family, they stayed for 7 years, and probably would have stayed longer but took advantage of the Obama dollars first time home buyer's credit.

I posted recently about a doctor that amassed a fortune in real estate.

. - Mom made the doctor prescribe be Ritalin when I was a kid and I have the attention span of a puppy - but damn - you're looking to move in together after being bf/gf for only a few weeks?