I'm a flight test engineer by day, currently stationed at Eglin Air Force Base, FL (just across the bay from Destin). 

Water, air, sewage?

I haven't had any problems at higher temperatures, but the lock itself is inside an air conditioned property.

I'm still up in the air.

I’m active duty Air Force and maxed out my VA loan with three properties.Birmingham has some cheaper properties, but may not bring the cash flow that STRs in Florida might bring.It all depends on your timeline, numbers, funds, and comfort level.

Some people are allergic to rabbit hair so I would need to get the air ducts and entire house deep cleaned if the tenant moves out. 

Just my 2 cents you are breath fresh air preach truth finally 1 other intelligent person beside cute blonde from ny. lol

I personally like it when there is a IRS lien scares the uninformed away and much less competition .. it also keeps those that MUST get a HML to pay off the cash they invested as quick as possible..

Like @Alan Asriants and @Matthew Paul said location, location, location, an area during the day and night are very different things in Philadelphia.While the cashflow might be great, the greater the risk the greater the reward, but there are still plenty of other areas where you can get 200-400/month without being near the largest open air drug market on the east coast.

I'd look into Air BnB, VRBO, Furnished Finder, PadSplit, and perhaps even booking.com (I know a lot of STR operators use this, not sure of MTR potential but worth checking out).