Sewer and water in my area is around 10k a unit.

Water galore.

As for the first, yes we'd be able to do that (for example, replacing a water heater which is the mechanical that's closest to the end of its useful life).

Section 8 can be a PITA in some areas with things like paying rent on time if there is a water stain on the ceiling.

First of all, let me pay my respects to the hardworking people in real estate and the treacherous waters they navigate—fronting hours of effort with only the chance of commissions and an abundance of non-forthright people out there.

I just don't want to buy that close to the water due to flooding concerns.  

For example we replaced a water heater recently.

A buddy of mine just built a duplex on the water in Placencia

As far as features, Rent Redi obviously blew everyone else out of the water.

I have warned countless people that the "new", "Cheapest", and "shaking up the insurance market" carriers typically come into the market under priced, have a wave of claims, then they either jack up premiums to survive or fire their staff to keep heads above water.