this is a follow up on my question on paypal integration. I'm working ona membership site for racing fans. My membership site has 3 membership levels - free, gold and premium. When a user signs up he/she can gets a free membership on the spot but has the option to upgrade to a gold membership for 4 Dollars a month or a premium membership for 10 Dollars a month.

I've gone through the paypal integration guide a few times though and have a vague understanding of how to get this to work. I think the recurring payments option would be fine enough - however I don't know how do I implement this in my system.

Like when a user decides to go for a paid account i.e. Gold or premium from basic - what should I do on both my code side and on the paypal account side - I'd really appreciate if anyone would outline what I'd have to do here.

Plus when a user decides to upgrade from lets say a Gold to a premium account - there is the issue of computing how much should be charged to upgrade his/her account eg: a user has been billed for 4 dollars and the next day opts to go for a premium account so assuming that the surplus for the rest of the month is 5 dollars and further from that all payments would be recurring 10 dollars monthly - how do I implement this?

And in case a user decides to downgrade from a premium account of 10 dollars a month to a gold account of 4 dollars a month - how do I handle the surplus which would have to be refunded for that month alone and changing the membership?

And like wise if someone wishes to cancel membership and go to having a free account - how do I refund whatever is owed and cancel the subscription.

I'm sorry if it sounds like I'm asking to be spoon fed :( I'm quite new to this and this is for a client and I would really appreciate all the help here and really have to get this working right.

Thanks again everyone - waiting for all your replies.