Tips for Selecting a Web Development Firm?
cyrano asks: "The organization I work with is looking for nothing less than a complete re-launch of its web site - upgrading from cobbled together static HTML and ASP pages to nothing less than a dynamic, database-driven site with a full-featured Content Management System and a secure eCommerce component. I have already collected proposals from several firms, each advocating the benefits of Java and Struts vs. ASP.NET vs. PHP...however, the technology used by each firm will only form a small part in my final decision. My true concern is ensuring that the firm I contract will be professional, cooperative, timely and will ultimately deliver their services as promised. What sort of questions should I be asking them, and what sort of warning signs should I look out for to make sure I find the perfect fit?"
Even though this was posted by an AC and modded funny, sadly in my experience it is mostly true.
Very few web development firms I have dealt with had any of these qualities, let alone all of them.
I think the best advice has already been given in multiple other posts: Ask for references, check those references, and check out their past work. Ask your questions of the references that they supply.
As for technology... This sounds like this will be a fairly involved site, who will support/maintain it going forward? If the answer is you (or internal staff), then you will want to consider technology you or your staff are comfortable supporting.