Depending on the type of "group home" (drug/alcohol rehab, handicapped, mental illness, elderly, etc.) you have other laws to make sure you comply with, and great point by David D Painter re insurance.

Squatters usually end up with trespassing and various other charges (criminal mischief, burglary, theft, usually drug and weapons possession charges or they have outstanding warrants for other stuff/ are on probation).

For starters, is the property you are selling a property you have held for investment (not a fix and flip where you are a dealer)?  

A dealer will offer you considerably less, one offered me $2500, so I figured if he was going to resell it I might as well just market it myself and it wasn't difficult to sell.

If you're doing a lot of flips, you will be considered a dealer since the income from an S-Corp passes through to your personal tax return. 

If so, what would it matter if the contract purchaser is a dealer? 

Contractors and dealers were so upset with us when we showed up with the new machine and asked them if they wanted to test drive it.

$100K In Cocaine, $65K Cash Seized Drug BustThis is what i saw when i looked up the tenants of the unit in a triplex i'm buying.

I'm new to investing and know a tenant that is either using or dealing drugs can be a big problem.

PA & OH allow 4-5 homes a year to be sold w/o a license; PA requires a vehicle dealers license for new homes, but a traditional RE license is ok for used homes.