Be sure you read the policy carefully.
Lets use progressive as a example ---
under damage to your boat, you have three ways they can look at paying for a total loss ( They are the ones that make that determination)
1. you can purchase -- Total loss replacement / purchase price coverage -- this provides replacement of the watercraft for the 1st four years from manufacture date--- after the 4th year coverage changes to purchase price ( what you paid for it with proof) -- so basically, if you have had this coverage on a boat you purchased new 10 years ago, and it was deemed a total loss, you would get the amount you paid for the boat 10 years ago. Generally, you can only get this coverage on a brand new boat.
2. Agreed value coverage - this is where you put a actual amount of coverage you want on the boat -- if there is a total loss ( again they decide) you get that agreed upon amount -- your premium is based on the amount you select -- higher the agreed amount, higher the cost.
3. standard coverage -- you get actual cash value for the boat
Unfortunately there are very few companies that write houseboat insurance AND are able to comply with Aramark's and the NPS's requirements for coverage. Be sure to work with your agent to be sure you have the coverage required. If you do not, you might be the one left holding the bag-- some of the largest companies are not able to satisfy the requirements , but would still be happy to sell you coverage. You get to find out about it if there is a loss----