Stanco Climate Control overcharged, charged me for items I didn't need, etc. Freehold New Jersey

This is a complaint against Stanco Climate Control, 4400 Route 9 South, Suite 1000, Freehold, NJ My husband and I are both senior citizens and he is a veteran and disabled. He suffers from COPD and has a very bad breathing problem and heart trouble. He has to stay out of the heat. I had a new air conditioner put in by Stanco 5 years ago. I called them 3 times because it was going on and off and wasn’t working properly. It took them 10 days to come down to look at it. The man from Stanco checked the refrigerant and said it was good and didn’t need any. He then put a capacitor in and the ac started working. My husband was happy but the man said we needed a new compressor and took the capacitor out and put the old one back in and left. He was only here for about 15 minutes. Another man from Stanco came the next day and said we didn’t need a compressor. He put the new capacitor in again and the ac was running. He said the part and labor were warranted for one year. He stayed outside by himself for a few minutes and came in with the bill. He charged me $119 for the capacitor (which you can buy the exact same one for $l0 at Home Depot….see enclosed item). He charged me $297 for labor (he was only here about 45 minutes). When I questioned him, about the labor charge, he stated something about the warranty which I didn’t understand. He also charged me $80 for two pounds of refrigerant after the man from Stanco who came the day before said we were good and didn’t need any. (I didn’t know about that until my husband looked at the bill after the man left and told me). He also said that if I wrote a check out to cash he would give me a discount. He took $16. off the bill. I only paid him because my husband was having trouble breathing because of the heat and we had to have the ac working asap. This bill is ridiculous! It really bothers me because I recommended Stanco to many friends after they put my new furnace in and my friends used them. Almost $500 is a lot to pay for less than an hour labor and a $10 part. I called them 3 times and emailed them since the day they fixed it and they have not gotten back to me to settle this. I really want some money back. They really ripped us off!