We are using it the same time as the SAH grant, but we needed the additional $$ to do everything. Our contractor just earmarked a part of the project that could be separated out and wasn't a requirement under SAH. He did a separate estimate for that, we took pictures and completed the form to submit. The money isn't in our account yet, but it has been approved. We're in the midst of renovations now, dust everywhere, and the HISA portion has been completed. HISA was very easy compared to SAH. If you don't need the money from HISA right now there really isn't any reason to use it yet. You can hold it for the future. It is pretty quick and easy to complete. The SAH grant on the other hand should be done right away because it is an administrative mess and takes a lot of time. My advice to everybody would be don't wait on SAH, start yesterday!
Our state, Virginia, also had a grant of $4,000 which was easy to do. So check for state assistance too.
Mary