I'm certainly not a tax expert so hopefully someone like @Steven Hamilton II can add to this, but yes if you buy and sell real estate as a business I believe you can be considered a "dealer" to the IRS, and you would file the income on Schedule C (self-employed) if you're a sole proprietor.  

Most are drug dealers houses.

This isn't the best area but it certainly isn't the worse.Some drug activity in the area but they move the corners they are selling off of every few months. 

Would it be a banker, a mobile home dealer, a certain type of inspector?

I also found he had added a unapproved roommate; this guy made HIS living selling drugs out of my house. 

I won't go on with the novel, but he are some other red flags: 1) When I showed up to the acquisition manager's house, his wife was running late as she was coming from two eviction hearings at court that morning. 2) At one point on the tour, a young man dressed in stereotypical ghetto ware approached both the PM and Myself in front of a house (I wasn't sure if he was going to try and sell us drugs or what) and said that we didn't look like we belonged in the neighborhood and "are you guys investors?".

I have video's of bugs, reported everything from the bugs to drug needles in the kids playground, and can prove there was a murder across the street just off the property.

Has the seller received any notice of foreclosure, if so you need to head the other way if you can't buy it, this is full of new foreclosure landmines, if no notice has been given then you can proceed on the creative side.If you are acting as an investor, you can do an installment contract, as a real estate dealer selling to a consumer, buyer tenant, you'll have federal laws to comply with, pretty hard to do now.However, I'm more concerned with, what appears to be, the  intent of avoiding the mortgage requirements.

As a dealer and a contractor I've often charged a customer to remove them in order to install a new one.

Has it ever been moved other from the manufacturer or dealer who originally sold and installed it?