We have had three companies out to bid our system. The range has been about $7.00/Watt to $8.25/Watt after all XCEL Rebates and federal tax credits are factored in. This is for a grid tied system with no battery back-up. So, for example a 5,157 W system out net cost will be $13,125.
Now that's just for the solar system. We also have to do a new roof at $8,100 and had to cut down two huge Spruce trees for $600 so you have to consider those costs as well. We need a new roof anyway but would have waited a few more years if not doing solar.
My wife and I also took a class on how to do it ourselves and that was going to be around $6.00/Watt. We figured it was worth $1.00/Watt to have it done, have the install company "float" the rebate, and have a 10 year warranty.
Edit: Additional costs