Re: How much is it to retolex and amp?
Vinyl is sold in yards, each yard is 36" long by 54" wide. You'll need four yards to go around your 4x12 cabinet, but since it's less than 2 ft. deep, the extra will probably cover the head. If you want to recover the back panel of the cab, that's another yard.
Vinyl can range from about $8 a yard to $30, depending on how fancy it is. I covered my DIY amp with vinyl I bought from
yourautotrim.com, because I wanted something different from the usual amp Tolex.
On top af that, you'll need a couple quarts of contact cement. If you hire someone to do the work, figure on 8 hours, but I'm not going to guess the rate.
Tolexing cabs id not really difficult, if you'd care to try it yourself. Google "Casey4s Tolex", and you'll probably find a tutorial that really helped me.