It is important to check the operation of the car heater and car air conditioner because these are expensive items to repair. You REALLY miss them when you need them and they don’t work.
To check the air conditioning, start the engine and let it warm up for a few minutes. Turn on the air conditioning. Unless it’s freezing outside (less than 32 F), your a/c compressor should click right away.
The air conditioning compressor should remain on for at least 10 seconds. If the compressor seems to turn on and off every 3 seconds, the system is probably low on Freon. Being low is a relatively simple problem to fix. Why it is low is almost always a more expensive problem. Within a few seconds, cool air should be blowing out of the vents.
If you don’t feel cold air, the automatic air conditioning may not be working. In addition to the fact that a car air conditioning problem can be very expensive to repair, this also points to the possibility of the car being involved in a head-on collision.
Check the heater.
Try all heater fan speeds. It is not unusual for some of the speeds to have failed.
A big problem with heaters is a leaky heater core. A leaky heater core only gets worse over time and is very expensive to repair. With the heater on, if you smell moist air coming from the antifreeze-scented vents, be careful. If the windows fog up, this is an indication that there is a heater core leak.
This is a relatively easy problem to spot and a very expensive problem to repair. I would skip this car and move on to the next one. Yes, there is always a next one. A little extra work now will bring you years of benefits.