as already mentioned, look at the larger container sizes as it makes it more cost effective.
I buy almost all my products in gallon sizes, some I'm going to start buying in 5-gallon sizes.
The Megs Pro line comes in larger sizes as do the Megs Detailer line. Megs Detailer line in particular not only comes available in the larger quantity sizes but in many cases the product is very, very strong so dilutes well making it even more cost effective besides being very effective, high quality product.
As a few examples, in the Megs Detailer line is D155 Last Touch. used straight it is an excellent QD spray. Dilute it 1:1 and it makes an excellent clay lubricant. Not only is cost effective, it also covers two uses, AND is an excellent product.
Megs D151 Paint Reconditioning Cream is an AIO polish and wax. Has the same polishing cut level as the excellent M205 so will remove minor swirls, etc and has a wax so when doing destail jobs it's also not only cost effective as a product but it's also very time effective. For the same time as doing a polish you are doing both a polish and the wax all in one step offering your customer a better value because they got polishing results which normally standard details don't offer. I use D151 on all my detail jobs unless the vehicle is having complete paint correction work done in which case I'll go the clay, M105/M205, LSP route.
Megs APC is probably one of the best cleaners out there and allows you to dilute at various strengths s very cost effective while the Megs Detailer line Hyper-Wash D110 dilutes at 400:1 so a single gallon container is making 640 gallons of wash for you!
I could go on but I think you see the point.
Duragloss also comes in larger quantities but i never used it to give you examples.