I'm still using my $100 NAPA IR gun that I bought over 30 years ago. It paid for itself the first day as it helped find a overheating problem on a bulldozer that I could not solve. Living in a small town I go to Ebay when I need something and it looks like for less than
$15 for one so buy two.
Probably the most unusual use is to point it straight up on a very clear day and see how low a temp... I've gotten a -20 which is around 30,000' up.:C