A big aspect of owning/running a boat, is the upkeep on her, & especially her systems. Which, depending on the boat's size, & her systems, can quickly become a fulltime job. Especially if there are a lot of systems, or they're complex. And such trends grow geometrically with boat size, as well as "stuff"/toys.
The big caveat to this being that when it's time for a major refitting, boat size defintely matters. As there are a lot more fittings & fasteners to rebed. More
hull &
deck to sand & prep for
paint. More spar fasteners, fittings, running
rigging, electrics, etc. to replace, or
repair.
Which, some simple stuff you can hire out if you've the coin. But other things really need an owner's touch, or at least their vigilant supervision. And around this time a lot of folks often wish for a 10' smaller boat. Especially as
sanding often demands wearing protective
gear, including coveralls. And if you're somewhere hot, the more time spent wearing such, the more miserable the
refit is.
Also, if/when you have to unexpectedly replace things like, an
engine, a
furler, a bad lot of rigging wire, your ground tackle
lost to a snag, etc. Then the difference in expense is noticable. Much as when you're replacing a sail. Or sometimes, 3+ So you may wish to run the numbers on such things, comparing a couple of boats/boat sizes to one another.