There are many things to consider when buying
Your boat handling skills will improve with experience no matter what level you are presently at, although getting there may be a daunting experience.
is where many come unstuck as they buy the best biggest than can afford then unexpected expenses come up and make the exercise very difficult.
Saying you will just charter boat to make money is easy to say, but make sure you know what that entails.
Taking strangers on your boat and letting them loose even if you are onboard controlling them is not for the faint hearted as they rarely respect your pride and joy the way you do. Especially if they consider they are paying top dollar for the experience.
As far as size goes, the overall length of a cat does not always compare to the space inside, my 40 footer has as much room inside as some larger cats and people are amazed when they come onboard. Also some cats just give you more cabins and heads as you go up in size.
Waterline is important and can give a better ride and speed, but so is weight.
Some of the “quality” cats also have larger weight than the cheapies and so their performance may be compromised.
Take your time and look at as many cats as you can and get as many rides as you can.
Unless you have money to burn I wouldn’t charter a boat until you have decided on a particular boat. Many owners are very happy to show off their boats and take you for a ride so you can see why their boat is the best.
You also need to decide what you are going to do with your cat. Are you going around the world or are you just going around the harbour?
There is a lot to think about and a reasonable investment in time and money.
At the end of your search the boat will feel right for you.
There is no perfect cat, just the one that suits you best.
Good luck with your search and enjoy the journey.