choose a boat?

[camp guy]

Have you considered a pontoon boat? With 5 kids and associated friends, finding a V-hull to house all these bodies, in your price range, will be tough, so maybe a pontoon would be the answer. The newer versions of pontoons come with plenty of power, current amenities, plenty of seating options, and walk-around space.

Sounds like you use the boat as a floating cottage, so why not go for the flexibility of a pontoon.