From what I've read, that if you plan to stay in your house more than 10 or 15 years, then it makes more sense to buy panels and other hardware yourself, but if your horizon is lower then you should lease them.
That said, purchasing the hardware costs as much as a car, so maybe can't do that.
http://www.npr.org/2015/02/10/384958332/the-great-solar-pane...