Bathroom Addition, Roof Replacement, Wood Floors - Galveston

[Kwanza P.]

Any experience replacing a roof in a beach town (Galveston or Crystal Beach in particular)? How much should I expect to pay and should I do this right away? Roof is 10+ years old. It's Asphalt and the home is steps away from the beach. How much time does this take?

I'm also considering adding a bathroom. How much should I expect to pay for this and approximately how much time? 

Someone painted floors in the beach house. I think it looks bad. How much should I expect to pay to renovate the floors? How long might it take?

LASTLY - is it a bad idea to convert a ground-level utility room of a beach house into a game room? Should I worry about flooding? Some carriers I've spoken too say they won't cover ground-level damage in a beach house. 

Thanks!