There are a number of solar panel distributors which may be able to serve you. Each will have slightly different models of solar panel, inverter, mountings and general quality. Given rebate incentives, there has never been a better time to look into solar schemes and choose one which is best for you. At the moment we have a solar PV penetration of around 0.9%, so the industry is poised to grow quickly over coming years. It is also sad to see that cloudy Scottland has a higher percentage of solar PV installations per capita (per household) than Perth, WA - Perth being one of the sunniest cities in Australia.
What to look out for with commercial solar installations
The main one is efficiency. Solar panels reduce their efficiency as it gets hotter. If you live in a very sunny area you will want solar panels which are made for your climate, and not Germany which is considerably colder.
Quality is another important one. The panels themselves are fairly standard however the frames in which these cells are mounted can differ in quality. How well sealed the frames are, as well as the quality and robustness of the overlaying glass are important considerations. Recently Perth had a major hail storm and some of the solar panels were wiped out. Most of these panels were older installations, however the newer glass can withstand bigger hailstones.
Warranty could be a consideration if you want to be sure that your solar panels will deliver 100% clean renewable energy over the investment payback period.
Size is another consideration. If you have a lot of space available, you may consider going for one of the lower output panel varieties. These panels deliver reduced power per sun exposed area however come with a significant price difference which often makes them the more economical option when space is not an issue. Of course on small houses, you may decide that roof space is limited and the higher output panels are justified. Keep in mind also the cost of mounting the panels and the installation costs including wiring etc.