User should be able to choose only one product

Hello,
In my site I need to have 3 kinds of users with different access rights. A gold user with all the privileges, a silver user with moderate privileges and a bronze user with limited privileges.
I need the user be able to choose only one of these access rights and pays based on what she/he has selected.
So my store will have 3 products (1-gold 2-silver 3-bronze) and user should be able to select one (sth like radio buttons) and pays for that. Can you please guide me how can I achieve this using hikashop?

I also like the user be able to upgrade his/her access right. For example if he has already bought a silver access right he might be able to upgrade it to gold. In such cases the user should be able to see only 1 products in the name of (1.upgrade to gold), so he must not be able to see the other product (upgrade to silver). How is this achievable?

Can all of these be done via free version of hikashop or not?

Best regards.

Hi nicolas and thanks for your response,
I found your reply really helpful but it seems you misunderstood first part of my problem. I need for example all the 3 products (gold- silver- bronze) are shown to the user but he only should be able to select and buy one of them. I mean if the user has already added silver to his basket he should not be able to continue shopping and add anything else to his basket. What is your suggestion about this matter?