||As a rule,
I can get the site 98% done inside of four weeks, but I find that ecommerce clients themselves need another month (or more) to add their products, get comfortable with the site, write their static text, set up an account with PayPal or WorldPay etc. It probably sounds a lot, but it's always more about your available time than mine.
Many of my ecommerce clients are already running a business or working full time and that's why they take longer.
Database driven websites, or those with some degree of complexity or database work involved. Well it tends to depend on the work involved, different from project to project. A month is generally a good rule of thumb, but once again it will depend on the clients time available and the spped in which they can pen or locate their content.
Given all the text content and pictures from the off, can usually be done in 10-14 days. But from experience we often wait on domain transfer, photographers, confirmation of content from business partners, the client writing the website content.
It's not a particularly quick process, but in the end the client has a website that they are happy with and that will really work for them.