I show my dogs - and I can give you a few tips. First don't buy stuff at Petco etc - very expensive! I purchase my products online, going to retailmenot.com to get free shipping or other discounts at the various online retailers. Pet edge, care a lot pet supply, entirely pets, etc.
The professional handlers that I had showing my dog for a bit actually get most of their shampoo at sallys beauty supply! I had always heard that the ph is different and would dry out the dogs coat - but they are constantly winning with their dogs and bathing them daily at the shows. However they do use a lot of coat conditioners on the dogs so that may make up for the shampoo.
There is a waterless shampoo that you can dilute in a spray bottle and spray onto your dog and brush them, instead of using wipes, would be much cheaper. The brands I have used don't have much scent so don't make my dog smell any different.
I bathe my dogs weekly in whatever shampoo is on sale on the internet sites, and I do use one awesome grooming spray when ever I think of it during the week. Its expensive but you dilute it way way down so really its not that bad. Its by Isle of Dogs and used to only be available at dog shows and on their internet site, but now they are in Bath and Bodyworks (but not the grooming spray I use). Its the Evening Primrose oil Grooming spray. Put 1/2 inch in the bottom of a big spray bottle and fill the rest with water, it turns a milky white color. It conditions the coat & skin and leaves a wonderful fresh scent. I have retrievers.
Hope this helps.