Before making a solar system purchase (or lease) be sure to:
1. Learn about the technology and typical costs (usually $8-$10/watt_AC)
Web Link
Web Link

2. Get multiple bids, and compare total system installed cost per watt. Be sure the bidders all use the same rating for the system size (CEC_AC kilowatts)

3. Get references

4. Check the seller's CA contractor license at Web Link

5. Check the company's status with the Better Business Bureau Web Link (although no one has filed a complaint on Beohana Solar)

It really is critical that you ask for and speak with referral customers. 9 out of 10 times they'll have only good things to say about the installer, but in the event that someone had a bad experience, you want to know about it before you begin your installation, not after.

Similarly, checking with the BBB and checking on their contractors license (as "Knows Solar" suggested) can be time consuming but is well worth it. If you're spending between $5,000 and $40,000 on a home solar energy system, taking a few minutes to check up on the installer is time well spent. I doubt there are many fraudulent installers, but it never hurts to double check.

Here's a good site for educating oneself on how solar works & the reasons to go solar: http://www.residentialsolar101.org. They'll also put you in touch with an installer for a free home solar estimate. That said, don't work with any installer who would charge a fee to give you an estimate.