Just my two cents here, but one thing to consider is that when making
an offer on the "real" house, he may have to include a contingency
about selling the "temp" house. The fewer contingencies, the more
attractive an offer to the prospective seller.

Also, there is a psycological aspect here. I found that whenI bought
my house, minor things that I couldn't even be bother to tell the
landlord about in my apartment, would inspire me to make 29 trips to
the hardware store. It is unlikely that you will paint an apartment,
but very likely that you will paint your house, particularly when you
are trying to get the best price for it when it comes time for the
upgrade.

Gwen