One thing I have come to realise, if you want to look after your car properly, you end up spending a lot of money... and then you just end up with hundreds of half used bottles/tins/sprays etc. Loads I never use any more simply because I have got better products and can't see myself ever reverting to worse ones.
With £100 I would buy:
- Chemical Guy's Extreme Wash N Wax shampoo (slick, there are a few other shampoos that are just as good but getting on the CG theme here!)
- AutoGlym Super Resin Polish (can use this on wheels and exterior windows too so great all round)
- CG's M Seal (I know its not the most durable sealant but easy to use and looks good)
- Collinite's 847 liquid wax (easier to use than the 486 is (guessing the numbers here but the liquid rather than the paste!!) and almost as durable)
- CG's New Look Trim Gel (Great for tyres, plastics and rubbers - don't like it on the inside though as too glossy for my liking)
- CG's Silk Shine - only just started using this, but works really well on the inside, leaving a smooth silky finish)
- Pretty much any glass spray for the inside. I currently have some Turtle spray I got for free and works fine, cleans the glass, enough said!
- A microfibre or sheepswool wash mitt. Would be tempted to go for the microfibre, they seem to work as well but last for longer. Just make sure to keep the grit out!
- Foam applicators. Get a few, they are cheap.
- Microfibre towels. Get at least 3. One for glass. Other 2 for polishing.
- Buckets x 2.
All depends on the condition of your car really, is it good already or need cleaning? These products are for if your car is relatively clean to begin with, i.e. need no real paint cleaning (in which case get a clay bar) and the inside is tidy.