Be prepared to keep your solar panels clean. The dirtier they get, the less efficient they are at generating power. While it is true that rain and wind can often take care of a lot of this for you, you do need to get up there sometimes and dust them off yourself.
If you are buying a solar energy system, make sure your panels can be easily adjusted. As seasons change, so does the angle of the sun. Your panels will need to be adjusted every three months or so. Make sure that you know how to do this or talk to your contractor about seasonal maintenance.
Minimize the upfront costs of solar panels by considering a lease instead of a purchase. This spreads the payments over a long-term period into monthly installments, so you could actually start saving money immediately. Still, consider how long you will be in that building, as the long-term periods usually run a decade.