I can make a call sitting here. It's extremely unlikely that you will
get back anywhere near the $3200 it's going to cost you. About the
only way I can see it making any sense is if you have a garage full of
junk and by adding the shed, you can move stuff from the garage and
make it look bigger and more attractive. Different buyers will have
their own ideas of whether they want a shed at all, what kind, what
color, where it should go, etc. Rather than pay you a hefty price for
a shed your wife happens to like, most are going to want to do their
own thing.

Ask a real estate agent for an opinion.