Air conditioning recharge

I have a 2 door 1999 Honda Civic with 110K miles on it. My a/c went out last week. I do not have a regular mechanic. What can I do to prevent getting ripped off? I fear that some teenager at a mass chain store will tell me to just recharge it and then I will be back a week later because it will stop working again and then they will say that I should have had other work done. What should I insist that the mechanic test or look at, and what ballpark figure should I expect to pay for the diagnostic tests? How do I know if my car is already equipped to take the new freon or if I need to have additional work done?
Thanks!

When recharging my A/C do I need to evacuate the system first & if so how do I do that?

If you're just adding refrigerant, there is no need to evacuate the system. If there was somepart replaced or a line opened, you have to evacuate the system using a vacuum pump.

My newly converted and charged AC worked for about 1300 miles until today, at 110 F outside temp the compressor didn't turn on. It worked in the morning while running errands.I tried pushing hard on the AC switch, but it still didn't work.
Any suggestions?

Thank you,
J.

We measured the pressure and it was in the low range. Tried to charge it with a re-fill bottle but it made no difference. The compressor didn't even kick in. Could it be a faulty relay or some other bad electrical connection?

I have a 91 Honda Civic, I recharged the AC with R134 because the person at Autozone told me that all I needed was the connection kit. The AC wasn't working for quite sometime before I did this. How can I tell if I messed up my cooling system? My compressor is still kicking on just fine. The AC worked for a couple of days then stopped blowing cool air again. Is there anything I can do short of taking it in to get repaired?

There was no dye added. The unit was completely empty to my knowledge.

I used the gages and got it to fill to the correct pressure, my problem is that someone said I may have messed up the system if the sytem was R12 and I used 134, I don't know what it had before but everything on the car was original down to the clutch so what ever it had was probably the same.

System is empty gauge states 0 psi. Nothing flowing from the valve if opened. Upon starting to fill with 12 oz can of Freon compressor kicked on and pressure rose to around 55 before the can was depleted. I drained the system again for a double take and same issue. Cannot figure why the compressor responds but the system's pressure is not properly regulating like it should. Compressor does shut off at high pressure and kicks back on if you drain the system of some pressure.

Did not pull vacuum. Low side is where the pressure rose. Will try pulling vacuum and seeing if that fixes the issue.