we weren't allowed to install anything. Wiper blades, coolant...not even new batteries in keyfobs! As an employee, if you touch someone else's vehicle, you are immediately liable for any damage done to said vehicle. Let that wiper arm slip and crack the windshield? It's your windshield now. Break the tabs on the keyfob while opening it? Guess who's buying the customer a new one? Yes, your employers insurance might and probably will cover it but most places don't want to take the risk or deal with the hassle.

As far as your AC home refill goes, don't bother. Your AC is a sealed system so if the refrigerant is low, there's a leak somewhere. Refilling it yourself will only delay the inevitable. It may be an expensive repair or it may not but get it fixed right and you'll save money down the road.

Nowhere in life does the old axiom apply more than in the automotive repair business: Spend a little now or a lot later.