Also depends on who is doing the work. Some marinas and yards only allow insured list of workers to work on their premises. Also as a general rule
- anything that you do onboard takes longer - every forgotten tool, every recut of something involves going to the car and heading back to where you prep things. Other than a hassle for yourself - if your paying someone else to do the work - travel time adds up.
and a lot of painting - esp interior
makes little difference - but otherwise I vote for not launching until you have all or nearly all of the cutting and fitting of pieces parts
installed. The job is done faster (cheaper) when on the land blocked up. Working on a boat is a lot like working on a house renovation
. There is an art to scheduling and sequencing the work that makes it go smoothly and more quickly without do overs and wasted money
I have the best of both worlds in that my 55 year old boat is kept at the dock at home with power and air lines run from my car garage/shop. But even then I annually pull the boat to do whatever is need on the bottom - the metal running gear
seldom can go any longer than that. I have even spray painted the decks and cabin
while in the water before with Awlgrip but when the hull
and bootstripe needed it the work was scheduled so it could be done with the rest of the bottom stuff while on blocks.
A lot also depends on your handyman abilities. Plus your willingness to invest in the proper tools needed. Good quality wiring crimpers -Not from auto parts
store - good table saw if actual remodeling of interior spaces are to be done, a variety of drills (straight - right angle), and IMO an occellating sander/saw like a Fein, torch, feeler gauges, multi-meter with clamp-on ammeter, etc. Not everything can be done with a jigsaw and a hammer.
Decide before you buy how much you are actually willing and capable of doing before jumping in. I wish I had a dollar for every project boat I've seen get started on that never made it to the water after a year or more being started on. Sometimes the yard bill gets higher than what they can sell the boat for. Seen too many times.
If your not really ready to take on a big project and finish it maybe you should spend a little more and get something you can use right away.