Incidentally, most repairs to an HVAC system are quite self serviceable.
The channel https://www.youtube.com/@WordofAdviceTV/videos has saved me a lot of money.
On a complete tangent on the topic of “home maintenance you should know”, hot water tanks should be purged yearly (to get rid of the debris collecting on the bottom), and have a sacrificial anode rod to stop corrosion and should be replaced every ~3 years (magnesium) or ~5 years (aluminum)