SE bikes...

IIRC DeCosters (made by the same company as Mongoose- BMX Products) were only available with the front triangle Cr-Mo.

Full Cr-Mo Team Mongooses only came in epoxy finish red or blue.
They chipped pretty easily.
Under the epoxy, they were nickel. Not as shiny as chrome but still pretty
Took quite a while to get all that epoxy out of the nooks and crannies.

I bought that frame for $50 (a LOT for a 14 year old kid in 1982) because the guy that owned it chipped the hell out of it and didn't want to take the time to strip the epoxy. His parents bought him a new Super Goose frame.

I was so poor, I couldn't afford a sticker kit, so I made my own rear triangle stickers from some of my mom's blank mailing labels and correction tape, painted like the factory stickers. They turned out pretty good.

Full Cr-Mo SuperGoose was the same frame, but chrome plated.
Cost quite a bit more.

80% of my stuff was bought used or traded for, though.
IIRC the only things I bought new were the crank, pedals and handlebars.
Maybe some brake HW.
The prototype Nitto SX stem was given to me by K&G bike shop who later became DK, manufacturer of frames and then complete bikes (with Mopar names, nonetheless). They gave it to me because I broke three Sun Tours in three months.