One of the two stabbed someone at a gas station - I recognized them from the news article (they had security footage), and they've been turned in to the police (the police have all their info, but haven't acted on it yet).

Section 1031 does not apply to exchanges of: Inventory or stock in tradeStocks, bonds, or notesOther securities or debtPartnership interestsCertificates of trusthttps://www.irs.gov/newsroom/like-kind-exchanges-under-irc-code-section-1031

Did you get a tenant estoppel form that detailed the security deposit rent etc. when you purchased?

What in your opinion is the best demographic to target for regular people who want to sell their house and allows me to get a great deal?

So when I returned home I went to check and both locks were functional, though I didn't open the door because I didn't want to trigger the security system.

Do I have the right to keep his entire security deposit?

By doing that you should be able to raise the rent and possibly the sales price depending on the demand.The best way to make more money is to be prepared to move to the hot areas and by buying small apartments and working your way up to make enough to be able to hire an experienced Property Manager or a Property Management Company to take care of the daily needs, both maintenance and occupancy,  that is experienced in that area or type and will report you regularly on what you need to properly oversee their efforts and the properties financial status.One good thing is that many smaller apartment complexes are owned by Mom and Pop. 

You might be better off waiting and regularly touching base so they remember your name at that critical time. 

Roofstock Zack: “We are making sure your PM, Marketplace, will receive the security deposit, the tenant info so they can collect rent payments, and the keys if available”.

the only thing I was trying to avoid was any major costs to repair that wont be covered with there security deposit .