I tried to build a collection système with ACF and relationship field. It’s work realy good in back office because I can easly link any CPT “product” to another CPT “collection”. And in the front-end I can beautifuly display an CPT collection with all product linked.
But I can find how I do the same process in front-end with an add button on CPT product. Theres is a way to quickly add or remove relation on front-end ? The best would be able to selected or create new collection post in same time with ACF to like it does on themeforest.
I contact few pro dev on freelancer.com and is french version codeur.com, but every time they give up ;(