Toyota Repair: A/C Repair, toyota camry, correct diagnosis

Question
I have a 1996 Toyota Camry with 86,000 miles on it. The A/C cools intermittently. It seems to cool better in the mornings but stops working. A repair shop checked it and said there was enough freon and therefore it is the compressor that needs to be replaced, which would cost $750.

Is this a correct assessment of the problem? Is $750 a fair price for replacing the compressor?

Answer
I don't know if it is the correct diagnosis and I would get another opinion, whether the compressor is at fault or not depends on the line pressure readings of the system and unless you can provide me with those I can't even guess what the problem may be, the price seems about right but I would have another place check it, try the toyota dealer for another diagnosis.