If that is what you want, then I suggest looking at
www.charon.co.uk.
It is asp based, and is pretty much set up for you to upload
and use straight out of the box (or download as it were). There are
some things you need to change to get the site to work with a
payment vendor such as PayPal or WorldPay, but, it is there and
waiting for you and your products.
Everything you mention is already built into the sample store
provided, all you need to do, should you want to, is change the
design or layout of it. It is also easy to add your own code to,
and above all, there is a very good forum should you need help.
Not only that, the extention that you buy as part of the
£25 price tag enables you to build your own cart entirely from
scratch, but I don't see any the need to when Jules has already
done an awful lot of work for you.
I have built several sites with it now, and one in particular
is sparking interest from other customers asking if they can have
the same. Based on the supplied sample, I redesigned and uploaded a
fully functional store in six hours - that includes integrating
with SecPay.
You'll learn a lot from the code supplied too.
HTH