If you aren't paying cash, your going to be getting a monthly reminder in the form of an extra payment year round . Find out what financing options are available. These things add up quickly. Don't plan on storing a 25' boat in a 24' garage. It doesn't work.
Gas consumption is a real factor in boats.
My walk-around has a 92 gallon fuel tank and a 200 hp engine. It tends to be thirsty. Be trueful with yourself regarding whether or not you are willing to foot the bill. Don't get into the rut of thinking that you'll always be able to find somebody who wants to go out on your boat and pay for your gas. Everybody you know will want to go out, but very few will want to pay or even help pay for gas.