FWIW I paid about $2500 to have my pool replastered with standard white marcite in 2010. I think if you get it done during the off-season you can get it cheaper. I had mine done in March.

I wouldn't do paint. You'll spend over $1000 and it won't be as good as real plaster. I did mine myself and it peeled after one season. It cost me about $600 and it was cheap paint.