Captive portal payment radius login

[skipzoid]

Hello.
I've been looking arround for a solution to allow users to connect, take a tiny payment from them via paypal and then allow them to use my wifi.

I have a look at paypalwifi which on the face of it seems to tick all the boxes, but its outdated, seemingly not supported and doesnt work, but the idea is sound.

Does anyone have and suggestions for an existing open source solution ?

using freeradius (which is already working and authenticating users)
payment via paypal ideally.

thanks in advance. ??