For occupied multi5+ we renovate one unit and the common area first & give the current tenants the first opportunity to move into the new unit.

(Upfront is most common).

These guys wanted to reinterpret the NWMLS lease I had, them that's not how it works, they just lost their minds digging up laws and forgetting common sense. now, i had offered to rent rooms to everyone  of the 7 unauthorized guest that had moved in if they came to me to get a contract. 

This fee will vary from PM to PM, but I've seen common fees between 25-100% of 1 months rent to place a new tenant.

I can see this for higher end A B type tenants.. were rent is 2500 or more a month.. first last is 5k and then you need 2500 security deposit so 7500.00 to rent.. which is very common in our market..  

The problem is I'm worried about buying this house from him because he has a fiduciary duty to get his client the highest price; but would it be proper/common to ask him if he'd be willing to find other properties for me and act as my real estate agent in a buying position? 

Also it seems common that the smaller local banks and credit unions are more flexible in their financing and underwriting as it appears you are doing

Jumping from 0 to 14 in one year is also common on these forums.

Multiple offers is a common strategy with wholesalers and investors buying off market.

This is a common practice (at least around me), and people are always willing to share what they know.