Ok, clarifying the question helps get better answers. Sorry I missed the focus of your question.
You don't need to spend the whole 225K on a boat up front, and it would even be possible to live like a king on a boat that cost less than the 100K you mention specifically, if the boat had been well maintained. You could spend significantly less than 100K on the boat, but depending on your standards, a refit
may be needed. If conducting (or even managing) a refit
is contrary to your notion of living well, then by something in Bristol condition. You'll pay more for it, but it may be worth it.
The monthly income is quite enough for a long while, even factoring in maintenance on a boat (as long as the boat is not enormous). However, as boats get bigger, more systems mean more maintenance and more money
, and other costs go up with length (dockage, etc). That's why it's a difficult question to answer without knowing more about the boat (and how many people are involved).
There are lots of threads in lots of places about the cost of cruising. You are fortunate to have much more money
to start this process than MANY others who pull it off (with a well selected boat). If you are sure this is what you want (or if you are sure you are at least willing to go try it and see), then I encourage you to go do it. Lots of great books
on how to get started. Good luck.