Well, I was in your position some time ago, and I believe I solved the problem with PayPal's Website Payments Pro (now $30/month) and EMartCart (
eMartCart:Free Shopping Cart for PayPal and merchant accounts. Add features for low monthly fee.). EMartCart costs $11.50 per month for unlimited transactions and merchandise now, has a script almost exactly like PayPal's, integrates with Payments Pro, and they have an automatic interface that will actually convert a page for you from Paypal to their script automatically and allows you to save the page elsewhere to check it out! I was up an running in literally an hour. If you want it, they also allow for both USPS and UPS automatic shipping calculations, although I don't use that feature. You can also do subscriptions, discounts and gift certificates.
It has the added advantage that customers don't know that they're dealing with PayPal at all, and with Website Payments Pro, you can also take telephone orders.
I have been very happy with EMartCart and their service for about three years now.
Thanks,
Marilyn Woodman
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