Specific Price For In-App Purchases (set by sellers)

If I was to set up a shop where the sellers input their own price for their items, is there a way to implement this given that Apple only has tiers available with increment? Apple only allows for XX.99$ amount and then starts jumping by interval. If there was a seller that wanted to sell a car, for 31.10$ (or 12,305.37$) by example, is there a way to do this? I am trying to find a way to move away from the tiers given the way I am setting up my app for sellers to input their own price. What would be a work-around, am I missing something? I was looking to implement something like this with StoreKit, but I am flexible to move to another product for anything that would make this possible.