Meguiar's Ultimate Paste Wax, need anything else?
 

My SLK and S-class are 10 years old, I usually bring them to a shop to get waxed. This year I have the DIY equipment.

The Meguiar's Ultimate and clay bars just arrived my door. I will wash the car myself, will my cars need something like cleaner polish wax before applying the Ultimate?

http://www.waxyclean.co.uk/media/cat...aste_wax_2.jpg


Halfords | Turtle Wax Restorative Cleaner Polish 500ml

http://i1.adis.ws/i/washford/297197?$pd_main$

If the cars have never been clayed then I'd take two runs at it or be really thorough with your single run. The amount of buildup on it will be astonishing.

Do that well and you can slap the wax on just fine.

What color are the cars?
Are there any scratches/swirls in the paint?

If the car is black and you clay it you can mar the finish easily and then it would be showing lots of swirl/spider scratches. A wax will not do much to correct that, to fix that it would need to be polished.
If this is on a silver car then just clay the car, use lots of lube on the clay to stop any maring of the paint. Then do light coats of wax to protect. Most paste waxes you can build up layers of wax on top of each other.

Thanks, then I can forget about the turtle polish wax.

both cars are silver (bluish silver paint)

Clay is a must! A cleaner wax is good if you have light oxidation. If your car is in good condition, a thorough clay topped with the megs wax should be just fine.

As mentioned, a good clay will rid the surface of contaminants. Make sure you are folding the clay bar often to keep the buildup of crud away from your paint. If you are using quick detailer for lube, i'd suggest wiping the car down with IPA ( isopropyl alcohol - you can buy 70% alcohol at most drugstores for less than $5 ) after to ensure the paint is clean as any lubricants from the clay lube could affect the wax bonding to the paint. It only takes about 10 minutes to wipe a full size car down with IPA so the time spent is worth it.