Thanks in advance for your expert help.

I'm probably the millionth person who has done this...so why has all my Googling turned up minimal help?

I'm building a website that needs to have the trifecta of parts.

1) eCommerce Shopping basket solution WITH time conflict\scheduling support.
2) User account management with login, support links, purchase history etc.,
3) Administrative back-end to administer both User accounts and eCommerce application

I run a small IT shop, and want to allow new customers the ability to pick a service of mine, schedule a time for me to perform this service (conflict checking), this would alert me via email or SMS, and then they would pay online via CC or PayPal.

I think ProductCart is a great shopping basket and it is probably the one I will use (if I can modify the time scheduler to my needs).

Could an ASP Programmer modify ProductCart enough to give me a scheduling feature that has conflict checking? I'd also like some jazzy drop down calendars to pick the day.

Also, does anyone know of a Web based Account Management ASP App...with an Administrative back-end? Any recommendations?

Sorry if the questions are pedestrian.

Thanks everyone.