What price should I charge someone to design an e-commerce website?

Heh, If I was using Joomla I’d be charging a lot, since I don’t like Joomla ;^P

In seriousness, it’s hard to know how much to charge. I have run into this problem before. It’s a lot easier when you’ve done enough sites to have a good idea how much time and effort it will take- at least I’ve been told it’s easier then, I’m not at that level yet by a long shot.
The most important thing is to get specific requirements beforehand. The customer will nearly always resist this. Make them sit down with you while you draw some mockups on a piece of paper or something. Map the site and determine ahead of time what sort of pages are needed, how they should be laid out, etc. Make it clear that the price charged is for that specific set of requirements and that any additions not covered by the requirements will cost extra.

You shouldn’t charge anything at all to design a shopping cart system… just install zencart or magneto on the server and then you can customize the theme for maybe 30.00 to 50.00 to hour. and if the customer wants help loading the items in to the system also then charge for that time… but I dont see the point to building something custom when there are already web services out there for that.

The lack of detail in your question indicates that this is going to be a learning experience for you – and maybe for the client, as well.

I’m not a web designer in any way, but I do know a little bit about business, which is why it seems to me that both responses so far are very good: you and the client should both have a very clear idea of what the ‘look and feel’ of the site will be. I think you should also have a specification to clarify the maximum number of simultaneous users will be, so that the site doesn’t crash unexpectedly if you design for ‘x’ number of simultaneous users and you hit ‘4x’ or ‘10x’ at some point – or if that does happen, at least the client is on notice that they have exceeded the design limitation.

Aside from having a clear idea of what the site should look like, the client should also be notified about what their own ‘maintenance’ responsibility will be, security issues they need to be aware and on top of – and you need to have some kind of charge sheet made up to include with your proposal for your standard and night, weekend and holiday hourly rates for special calls and emergency support. If the client is as new to what this all entails as you are (which is not a ‘bad’ thing, after all) then they will probably need some hand-holding after the site is operational, and you’ll need to include rates for that. (Your proposal should also include a specified amount of hours of classroom and on-server training for the person or people who will run the site day-to-day, and a rate for make-up or additional training.)

How many hours do you anticipate the work taking? Estimated time X $50 X1.2 (to allow for 20% overage/1 round of changes) + estimate for stock photos. If shooting photography for site, 10 years ago, I was paying $50 for a catalog shot.

Clearly specify how much rework is included in your costs, and what the charge wil be for re-dos.

@CyanoticWasp Sufficient provisioning of the site certainly needs to be looked after, but it’s not necessarily something over which the web developer will have any control. If @roseped06 is hosting the site in addition to building it then the price should be much higher- and if the hosting is someone else’s bailiwick then it should explicitly state in the contract that outages due to traffic are not something for which @roseped06 can be held liable.
I’ve been on both sides of this, and I would have to be really desperate before I would take on another web-dev project unless I was also hosting it. I’ve had way too much trouble with shared hosting in the past.