I need a solution like this
To add to a Wordpress site
When you fill that form in it jumps to PayPal with the fields populated and where you can log in and pay.
see this shot
Do I need to customise contact form 7 or similar or is the a ready made solution?
There is an Add-On for Gravity Forms ( a paid plugin ).
If you are interested, I can set it for you.
Also you can use CF7, see this [[LINK href="http://contactform7.com/redirecting-to-another-url-after-submissions/"]]http://contactform7.com/redirecting-to-another-url-after-submissions/[[/LINK]]
Again, if you need, I can code it for you.