Its an issue, you need to have a good understanding of it. For starters has the park ever flooded, has the park ever flood historically, what was the impact? Can you replace homes based on current ordinances.
Whats base flood elevation. Right now, the property we are working on is in flood. Base flood elevation is about 1 -1.5 feet below the park. The mobile homes have to sit 12 inches above base flood so about 2-2.5 feet above base flood. Spot checking a few mobile homes, they sit that high anyway. So while technically the park is in a flood zone, for me, i was able to be comfortable with it. The homes are technically not in the flood zone ( but they still are) as they sit higher than base flood .
Also the fact that Houston just went through Harvey and this park had no issues ( and i saw how our other parked faired here , it got my comfort level to be ok.
Thats not to say its risk free but i tried to evaluate as much as possible and really understand what i perceived as the risk.
Some other factors might be who owns the home, you can obtain flood if you factor the cost on POH , perhaps mandate TOH carry flood.
While it would be great to have a perfect park in every way, you have to really analyze each deal for your comfort level.
If its a known flooder that washes away homes, i would certainly run for the hills . Try and do what you can to research and really have an understanding of this variable.