I work with an HVAC extended service warranty company. Recently we had a contractor who was servicing one HO's barely 5 year old Lennox XP13 heat pump, up in Quebec Canada. I spoke with the tech who said there was an "obstruction" in the condenser coil that "could not be found or repaired," and he sent us an estimate for a completely new outside unit. When we asked for a detailed service ticket, he dismissed us saying "we don't use those for residential jobs, we only issue invoices."
So, another local contractor was called to get a 2nd opinion. When he got there, he told us that the 1st guy had ran off with a dual capacitor, and found the system overcharged by 5 lbs. R410A. He said he can put in a new capacitor and TXV and adjust the charge, and sure enough that did it and left the HO with a working AC for less than a quarter of the cost of the 1st guy!
Needless to say that 1st guy is not gonna get a call from us again. Guess he was looking to get a sale rather than fix the problem!!