helenp - 8:22 pm on Dec 7, 2012 (gmt 0)

I used an interstitial confirm/proceed-to-payment page to allow recording the essentials of the transaction before sending the user to PayPal for payment.

Not sure I understand, do you mean record all the vars such as arrivaldate, hour, taxi needed etc? Or do you mean just a confirmation page?
What I am afraid of that once they enter paypal they dont like the method and decide to not continue.

Maybe I could add all details to a temporary database without doing the bookings, send the id to paypal, get the id and then just do the booking just passing the details from a table to another and do the email or pdf file as a confirmation.

However the risk of doing the booking after payment is even is very low is that the owner can block for his own use or another cliente can book at the same time and the payment has already been done.