A web form that calculates the cost based on google distance/time + passes to paypal

I'm looking for Customers to be able to input their postcode and for the system to calculate the cost.

This is derived by:

1. the cost of the selected service (fixed price) +
2. Google estimated travel time at £1 (i.e. return x 50p) per minute +
3. Google estimated travel distance at £0.90 (i.e. return x 45p) pence per mile.

The 'from' location will need to be a fixed location near my office.

I want them to be able to then select a date from a calendar/diary and to pass the figure to PayPal for payment.

***I want all of the pre-quote information (and ideally the quote) to be saved for follow up if they don't go on to pay/book - IDEALLY populated to my CRM system - API is simple apparently, docs attached***

I want the service costs, multiples and 'from' location to be editable in the back end by me. I want this to be an embeddable form on an existing website and be coded to fit in as part of the site...

The final form will need to look like part of the site, so adopt the sites coded styles if that's possible; is that possible?

Please send URLs to any past work that you think shows the sort of thing/quality you can do

Thanks for looking.