Shampoo and Conditioner for Remy Extensions

Hi 🙂

My extensionist suggested a number of brands to buy in preparation for my micro ring extensions from drugstore brands to pro brands, and I'm curious if anyone has any personal suggestions? I don't mind spending more than I normally would on shampoos (why spend all that money on extensions if you dont spend the money on maintenance?!!) However when they get as expensive as £15 each I wonder if there's a product that's just as good for a bit less? Or if there's a stand out product that is really worth the price? My own hair is coloured so ideally needs to be a colour treated one..
Also, I bought a Tangle Teezer-alike and have heat protection spray.. what other products do you recommend buying to help the maintenance?
I look forward to responses! 🙂 x