I painted the outside of my motorhome with International white exterior paint £15, 2.5 ltr.
This was recomeneded as it suited metal and fibre glass surfaces, I applied it with a small sponge roller that you can buy in any DIY shops £5 tray included.
You can not tell if were sprayed or not and the finish is like glass, no need to spend hundreds on paint etc.
Tim
July 2011