I have lived aboard my 30' boat for almost a year and a half. I'll second a lot of what is said here - keep tools, keep pots and pans, dump your small appliances.
Also go sailing! A 30' to 37' range is a huge difference in boat sizes and you may want to sail on some friends boats or in a club to see what you are comfortable with (and can handle). It controls what you can store on the boat too. Singlehanding is always tough, and smaller boats are easier to handle when you are learning in my opinion. (full disclosure here - I'm pretty new too, and am very low down on the learning curve.)
I reduced my stuff a lot before I lived aboard, but did end up getting a storage unit (5' x 5') for a while. My experience is that for the price of storage, you can replace most or all that you are storing for less anyway. I should have gotten rid of the stuff to begin with.