<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Here is IRS Form 5695. You can hand them a copy and they can make the determination themselves. As Allan says, we ain't tax advisors. I see on the <a href="http://dsireusa.org">dsireusa.org</a> website that it says that the PV system does not have to be on your primary home, but my reading of this form would seem to indicate otherwise. It defines a home as:<div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; font-size: 11px; ">Home. A home is where you lived in 2012 and can include a house, houseboat, mobile home, cooperative apartment, condominium, and a manufactured home that conforms to Federal Manufactured Home Construction and Safety Standards.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; font-size: 11px; ">It also defines a "Main" home:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; font-size: 11px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; font-size: 11px; ">Main home. Your main home is generally the home where you live most of the time. A temporary absence due to special circumstances, such as illness, education, business, military service, or vacation, will not change your main home.</div></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; "><span class="Apple-style-span" style="font-size: medium; ">Now, perhaps an expert bean-counter can work his/her magic on that, but methinks we'd be dumb asses to try it.</span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; "><span class="Apple-style-span" style="font-size: medium; ">Bob-O</span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 8.5px/normal Helvetica; "><span class="Apple-style-span" style="font-size: medium; "></span></div></div></body></html>