Shop upgrades.

Hey all. I have been recently working on some plans and upgrades to my shop. I have some new l.e.d. bulbs coming to make things a bit brighter. The inside needs some serious help. It had some bitchin 70s wood grain paneling and insulation that is filled with mouse turds. I was wondering if anyone has a suggestion for spray insulation. My thoughts are getting a kit to do it myself, and then put up steel siding. Probably going to attack this one wall at a time. This is a 30x50 building.