.- They came back at me with 6 months free, no rent increase until 2022, AND I need to replace the windows, submeter water, replace some decking, do landscaping.- I am just about to come back at them with no free rent, but I'll pay for their build out up to the value of 5 months of rent, plus windows/meters/ramp.Now I'm realizing that that whole package is a ton of money, and I won't make any money for over a year.

Well I’m glad I did be 2 weeks after closing we got record floods and this property got 7” of water in the first floor.

If yes, then you may want to consider it as you can upgrade with a better water heater and HVAC over time (or if you sell, maybe the next buyer can put in a hot tub;).  

Had a black water back up.

We divided the lot and are building two new ground up vacation homes right on the water.

For example you can plan the life expectancy for a new water heater in CapEx and divide it into your month expenses but if it goes out tomorrow, you need the reserves to cover the cost. 

Water heaters, dampness, foundation issues, control panels, the pricey stuff will show itself.

We are in the very early stages ofdevelopment (many calls/visits to Planning & Zoning, Landsurveyors, county water & sewage dept, etc).

I'm not a contractor but I've read that foundation repairs can be a huge expense, and tearing out drywall to fix water-logged wooden studs could be as well.Out of curiosity, where do your monthly income and ARV estimates come from?

Water is bill backed via flat RUBs at about 1/3 of the actual cost.