Downsizing to a 2320 just seems kinda bizarre to me. A 3720, in the
grand scheme of things, is not that huge of a machine. If you -like-
the machine, I would keep it. That is the most important
thing, period. One thing to keep in mind- even with the
low hours on it, you're still going to take a $$$$ hit when you go to
roll it over.
Not to get personal, but if your wife mentions it constantly it sounds like
the nag factor is at play here. A lot of women can do it, and they have
this sly way of trying to make their husband/boyfriend feel guilty about
something without being a severe pain in the *** about it.

It sounds
to me like that is the core of the problem more than anything else... if
she didn't mention it you probably wouldn't even fathom getting rid
of it. I would talk with your HOA/RC people about your desire to build
a structure to house your tractor. One thing to keep in mind- the rules
might be one thing, but if it is a committee they generally can override
them. HOA's suck but unless the people in charge are all terrible you can
often come up with something that is agreeable to them.
-Mike