The first and most common system connects your solar panel installation with the main electricity grid. This Grid Connect system allows you to feed energy back into the grid through your meter, and be financially rewarded for it by your energy company.
The other is a 'Stand-Alone' solar power system for remote properties where the cost of connecting the solar panel installation to the main grid is prohibitive. The system charges a battery bank, which in turn is used to power a house. A generator is usually kept available to back up the battery system.
We did not "lease" for the issues of maintenance, ambiguous repair and insurance loss issues and my guess is that it would be a complication to have a lease that must be assumed on a system. If you are doing it for yourself and are not planning on selling - go for it. If you want to sell down the line, buy the system and finance it if you must. My opinion for what it is worth!