This article describes who we used to insulate the existing walls in our home.
We used J&L Insulation. 619-561-8632 They will come to your house, measure your walls and subtract the windows and doors and give you an estimate based on the sf. Then you can check SDG&E’s website for the rebate. Currently it says the rebate is 15c sqft.
Ours ended up being $680, but we didn’t do the kitchen because we didn’t want to drill holes in the wood siding and it was too hard to get to from the inside because of the cabinets. We also didn’t do the wall that is shared with the garage or any of the garage walls (I don’t think the rebate applies for these walls anyway, but I could be wrong).
One thing we did wrong was we painted the exterior walls before we insulated. We should’ve done the insulation first.