lol - I thought about plastic after I sent my original. Plastic would
work fine too - some polys hold up better in inclimate weather than
others but it's a less expensive solution than metal these days.
Sounds like the estimated work approaches a new unit so if your
existing one has life left in it, you might as well get the bang for
the buck and run it until it fails. I've had a WIDE variety in
experiences with service guys too though so it may pay to have another
company take a look and give you an estimate. One company I am
familiar with sells way more compressors than they need to, for
example.

My air conditioner is about 13 years old. The guy suggested I should
replace the inside unit and the outside condensor (3 ton) for $3,000 total.
It will be Payne. Is this reasonable?