Connect php website form with payment processor

Dear experts,

I'm currently redesigning a website for a chap who wants to sell HIPS packs.


When ordering a HIPS pack at the moment all the site does is send a large form to write to a database where the client can see all the info in an admin area.

Please see the form: http://www.hipsxtra.com/order.php and enter 'che' in the code box

What the client wants to happen in the new site is to retain all the form elements and functionality except when you click the order button it also takes you to a securetrading.co.uk webpage where a single payment will be made to order a product. And thats it.

I can do the site design but need someone to quote for making the order button both write to the existing database with all the details and also redirect to a payment page (no form details need get sent along with to the payment page other than customer name).

There may be a few other bits and pieces along the way but essentially its the payment link.

This is not a massive job and still at the quotation stage but if someone could give me a one-off cost to fit this one in (within a month) that would be great.

Cheers

Chris