hi just bought a mk4 5 door golf 1.4

as my new project
all my old project were high power jap cars so this is a new area to me,
i have a few questions about the work im wanting done on the golf,
1) im want rid on the bump strips on the doors and the bumpers, am i able to take them off and get the body shop to use filler to smoth them over or do i need to weld a plate over the indent on the doors? also what about the arial on the roof? would filler do or will i weld a small plate over the hole?
2)what better for going low? Air Suspension Kits or coilovers? pros and cons? what kind of price is Air Suspension? i found a kit fitted for £1500 wasnt sure if that was abit cheap?
3) i have a mint set off 18" RS wheels although not sure if they will suit the dub look?
thanks
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