Questions relating to preparation

Nice good evening community, forgives if I set up a thread but after about 30 pages read and a lot of information that I partly knew, but I don’t have to answer the questions completely! As shown in the profile I lead a BMW 650i convertible (color: carbon black, basic color is dark blue, which looks medium blue in the sunshine, in the evening like black), cover color: beige. I would like to prepare it in the area Frankfurt I am not from the group: what? 120€? We agree on 99€, 1€ for the coffee, but would like to get a very good result, especially, as mentioned above, because of this “special varnish”. I have the following offer at hand: 300+VAT. for multi-stage paint treatment, total duration 2-3 days, then with Nano would cost 100+VAT. Supplement, can also mention the name if desired, is located in Bad Vilbel. Question i The range ranges from 100€ to 600€. Some need half a day, some two, but of course you don’t know if it’s actually polished for 2 days? Unfortunately, no one can give me any information about the products used, of course Swizöl or the like would get me to spend more in the direction of money. I’m open for any opinion and advice, thank you very much. Ahja, the cover was impregnated by BMW, should or can I still use a little fa Make it refreshing?