Carefully consider the types of solar panels you plan on having installed. Long ago, if you didn't have enough roof space, you'd need very expensive high efficiency mono-crystalline panels. There are now more advanced polycrystalline panels and even thin film panels. If you've got enough roof space, you might wish to look at the size of the panels in relation to their output capacity to avoid having insufficient panels that you need more of later.
If you're thinking about installing solar panels to generate your own electricity, make sure that the roof you'll be installing them on gets plenty of good sunlight. Good sunlight occurs between 9am and 3pm. You'll generate the most electricity if your roof receives full, exposed sunlight between those hours every day.