We have had units with every heat option (our 2 units with radiant heating have had the heating destroyed in a fire and are currently being rebuilt without radiant heat - ceiling radiant heat is no longer an option (it also is inefficient)).  

Due to my own ignorance (no denying it) and the repair company's recklessness and negligence most of my plumbing was destroyed in the repair process, costing me tens of thousands of dollars.

My first flip was a flop and I made 4k - essentially nothing and spent 1.5 years of headaches and TONS of time.I'm on my second flip which I hope to make some money next spring, praying Fed doesn't hike between then again and destroy the market.I really like the 70% rule but it's unreasonable these days unless you're talking about high end illiquid markets, 15% is more realistic.

Also rentals I no longer do here because tenants destroy everything, so that I would definitely not recommend unless you are living in the properties and keeping a close eye on things yourself.

The deal braker in AC is the flood insurance on some homes destroys any possibility of cash flow Still a lot of condo's for good sales or Auction property if you have all cash

Tenant basically destroyed the unit, requiring repairs.

Pets are a personal decision, you can increase the rent by $50ish/ month and keep that but they also create lots of noise, almost always have accidents in the house destroying flooring, tri and doors, and create extra messes that have to be remediated when tenants move out.  

The tenant destroyed the house.

There are 3 baths in a stack, this way the inevitable leaks don't destroy drywall, and the plumbing underneath is accessible.

All it would take is one nasty tenant to destroy a lot of income.ThanksOhio Buckeye