2015-04-08 15:20:52 -0500
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We have a stringent process for accepting installers into our network in terms of their quality and expertise, but have no rules regarding how they set their prices within our Solar Marketplace. In this respect, when you get quotes from our installers, you are seeing a fair representation of the offers that are available in your area.
We actually encourage you to go out and explore options outside our Marketplace in addition to the shopping you do within the Marketplace. Even if you don't end up choosing one of our installers, we're sure that you will find it useful in narrowing down your options. Read more about why you shouldn't shop for solar without EnergySage (whether you buy through us or not).
That being said, our data to date shows that customers who shop for solar using our Marketplace can pay up to 20% less for their systems than those who don't. This is because when someone shops on our Marketplace, they can easily compare quotes on an apples-to-apples basis, making it easy to negotiate a better deal. We also encourage our customers to be well-informed about the ins and outs of going solar with our extensive resource library, which we recommend you check out as you do your shopping. Getting educated about solar is one of the best ways to ensure that the decision you make in the end is the right one.
You might find the following links to be of further interest to you:
How to choose a solar installer
What questions should you ask your solar installer?
(PS. pete-kunsaitis brought up many of these points in his response to your question. Thanks for the praise, Pete!)