I think a lot depends on the neighborhood. If these sheds are very
common in the neighborhood, it could add value; if they are rare, it
could detract from value. The only time I have seen a home addition or
remodeling (other than cleaning the place up) add value was when my son
and I built a pergola on his back patio. His home was the only one in
the neighborhood (San Diego) that didn't have one, and when he
refinanced a few months later, the appraiser said the pergola had added
$1000 to the value of the house; not bad for less than $200 of materials
and some sweat.

MC wrote:
My wife and I are having a disagreement on whether or not to purchase
one of those Expensive ($3,200) garden sheds. (Looks like a minature
house)She wants to buy it Regardless of the fact that we plan to sell
our home in about six months.I do not want to have the thing
dis-manteled and moved to our new home so, I want to wait!She says that
this (minature house) will add to the selling value of our current home
.. I am not so sure.Do these minature houses actually appreciate or add
value to a home for sale?I REALLY have my doubts.Thanks Everyone