2011 camaro check engine
 

I just bought a 2011 camaro rs and the check engline light was on . When I went to auto zone the codes were p0420 bank 1, p0430 bank 2 and showed up 4 codes . The dealership said the cost was gonna be $1800 but I don’t have money like that, I’ve notice that the car rpm bounces a little and it idles I bought some 02 sensors online and having a mechanic put them in Friday . Any advice ???

What were the other codes?

What did the dealership tell you was the problem?

More information is needed.

These are the descriptions to the codes you provided.
P0420 Catalyst System Efficiency Below Threshold (Bank 1)
P0430 Catalyst System Efficiency Below Threshold (Bank 2)

Run a can of Seafoam along with Premium gas. Those codes indicate you most likely have carbon build up on your O2 sensors. The premium gas will deposit less carbon and the Seafoam will clean it up. $12 can is much cheaper than new O2 sensors or a new CAT.