Re-Spraying a Car at home.

Hi,
I have a Rochdale GT, it is currently bright yellow and did a previous owner paint brush with Valspar in about 1997.

I was thinking about repainting it over the winter.

I would either use enamel like Techaloid coach enamel with a thinner and spray it on or use a protection coat and use cellulose paint.

Could one just sand it down a bit and spray over it again with out priming it again?

Is it easy to do it in your own garage?
Would a £100 compressor and gun surface?

Can you still get Valspar?

Anyone any ideas?
Thanks William