How much is it to replace a 36 gal fresh water tank?

My dad thinks that we should not get a trailer that has had a tire hit the bottom of it. He's been RVing for years and a couple of years a ago they had a blow out and it ruined the bottom of their trailer. They had it fixed but the trailer was never the same. The slide kept messing up and some other things. My dad said If in fact it was just the fresh water tank and that's it that was damaged it wouldn't be an issue other than getting it fixed. so I think I will just end up getting the jayco kiwi.