In most states after a certain period you can claim ownership thought "Adverse Possession" Keep in mind it takes 20 years in MD so it may not be a very practical option.

The only way it is illegal, is if you are selling Real Estate without a license.... if you are simply assigning a contract for a wholesale (matchmaking for a motivated seller and buyer), you are not selling, so it should not be illegal to practice in that state or any other state.  

There is no practical way to evict someone, I had to pay a renter to leave.

I could make improvements over time, and maybe some day when I either have more $$ or that golden unicorn buyer comes along, I could even turn it back to single family (though I honestly could never see myself needing more than 3000 ft2).

Just curious how the board feels:If BP is made aware that someone is blatantly posting false information to sell their service, loans, homes, investment, etc. should BP remove the offending post and possibly offending member if they continue the practice? 

Think of this as a learning lesson and an opportunity to improve on a process with the pm.

Now the seller, since the deal didn't work out, is accusing me of practicing without a license.

I worked 10 years for the consulting arm of a big 4 accounting firm, helping Global Investment Banks, Insurance Firms, Multinational Asset Managers, and Hedge Funds improve their back office operations, specializing in implementing investment performance measurement systems.

Two ways I believe, % of value  of the improvement and actual cost.

Bad areas have their challenges but there are ways to invest properly and and you can even improve the property and the tenants in the property if operated properly.Management is the number one factor.