Your local library may have one of the $15 ones for loan. My library has a home energy kit that includes a killawatt and this and a few other things as well as an instruction booklet and your own notebook for results. A few years ago we had a thread where we found that people from all over the world, including several Australian states, had stuff like this in their library, so it’s possible that yours has stuff. The thread was about killawatts, not the thermal imaging gadget, but my library kit includes both, and yours may too. The first time I borrowed the kit, I had to wait for a while, and the weather was pretty average, so it wasn’t much use, but then I borrowed it in the middle of summer and got great results. They had increased the number of kits and there was no waiting time.