A/C- blows hot air

Hi im new here and i have an 03 audi A4 1.8T CVT......i bought it at the begining of 04 and my warranty just ran out.....and they refuse to look at my ignition misfiring.......and ever since i bought the car it has been in the shop every other month....not exxagerating....problems listed below

ESP-Malfunction brought in 13 times finally fixed

Ignition coil- typical problems i have heard

Cup holder jammed- no comment not a big deal

Sunroof wouldn't close-not too big of deal got it fixed

A/C- blows hot air- some tubes and pumps replaced twice

Back window button not working- fixed....not a big deal

now i am at 51k miles and my car seems like it is misfiring and not turning on till after two or more tries....maybe its the spark plugs? but i took it into audi and they were gonna charge me alot of money just to look at it.....they wouldn't even make an exception even though my car has been such a lemon....what do you guys think i should do? Any advice would be appreciated

thanks

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