bbPress.org

1) just use the

[bbp-single-forum id=$forum_id] – Display a single forums topics. eg. [bbp-single-forum id=32]

shortcode on the page to do that

2) That can all be done using coding, but would require a lot of code and expertise both within bbpress/wordpress and to link it to a payment product to take the money, and you’ll lose a lot of revenue in commission on 75p payments on say payal, who take a 20p a transaction charge as well as 3.4% commission.

Ballpark say £100-£200 for a coder to write that all for you (without looking that’s the sort of figure I’d expect to charge to write that, but it could be a lot more)

You would do better to look at a ‘membership’ site plugin, and take a payment per say ten ‘ads’, and use something like ‘bbp notify’ to know when they’ve posted, and a simple excel spreadsheet which you manually update. Then suspend membership or block posting when they have used up their limit.