On the assumption you have a black Elgrand, then I can recommend poorboys black hole. It's a glaze (polish with fillers), but brings up black cars lovely - I use it on our legacy. Normally around the £13 mark for just under 500ml if I remember rightly.
Poorboys Black Hole 473ml at the lowest UK prices from Car Parts 4 Less UK’s No.1 for Car Accessories, Car Styling & Car Care. Buy today Online, In store or by Phone + Branches Nationwide – Next Day UK Free Delivery.
www.carparts4less.co.uk
A good small bottle (250ml) of shampoo at a reasonable price for you to try (free delivery):
Elite Shampoo Is A Scented Luxurious Shampoo That Cuts Through Dirt And Grime With Ease Without Stripping Existing Layers Of Wax. Elite shampoo creates a copious amount of suds and specially designed lubricants give an ultra slick feel that lasts all the way through the wash process. Our Long...
dlsvp.com
And for a wax, I've gone back to my Meguiars Next Gen wax - even puts a shine on the white bus (hard to get a good shine on white). I only went back to it as when I sorted my garage out over the winter, I found I had a full unopened bottle so decided to give it a go again. I'm that impressed on the finish with it using my DA polisher, I may stick with it now (again)
Meguiar's ME G12718 NXT Generation Tech Wax 2.0 Synthetic Liquid Car Wax 532ml : Amazon.co.uk: Automotive
www.amazon.co.uk
Hope that all helps
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