How do you tell clients there are rules they must accept to work with you? [See details].

I’m an ecommerce developer. I happen to work almost exclusively on the Yahoo! Merchant Solutions Store platform. As a “Yahoo! Small Business partner”;http://ysbdevelopers.com/, I have access to only certain areas of the Cloud that the Yahoo! Stores reside in. I can fiddle with the database of product information, customer service pages and images that make up a typical Web store, for instance. I can revise the query language (proprietary RTML, but similar to PHP or ASP) that converts database information into HTML pages. I can make changes to the CSS for the checkout and customer registration pages. I can even use the available Checkout System API to make a few more fundamental changes to how the cart works. But neither I, nor any store owner can access the underlying CGI scripts that give life to the shopping cart, or that operate the site search function and customer registration. For obvious security reasons, only Yahoo top-level Engineering has access to that scripting.

Right in every proposal I send out, I define how the database of products must be structured in order to be recognizable by the Yahoo! back end. I define how images have to be named, as well. I note that it is possible to avoid these constraints by entering every single product in the form-based CMS that is the Store Editor. But I warn them this approach is time consuming, and for stores that will have large numbers of products for sale, it’s much faster to assemble a database in Excel, gather images named to match the ID of the product they represent, and upload the whole thing in batch mode. I also stipulate that our firm will quote doing that should they so desire, but tell them it is probably better that they do it, since they are already familiar with their product line and with what drives their customers to purchase items in it. I tell them that the proposal, as sent, does NOT include pricing for uploading, database creation or editing, and image processing services.

I guess it’s the Americans don’t, or can’t, read problem—but despite all my best efforts to disclose up front how building a store works, all too often customers sign up, then get livid because I can’t make the Yahoo back end work they way they want it to and not the way it actually does work—the way I defined it as working in the proposal. How brutal must I get to avoid this bozo factor. Can I even afford to try, or would the level of preachiness required lose me so much business I’m better off just listening to their whines when they come?

I’m sure I’m not the only person delivering professional services to have encountered this problem. Whether you work in a similar industry or a very different one, how do you avoid getting the client from Hell, or if that can’t be avoided, at least surviving the onslaught of insults they hurl with some semblance of your dignity still intact?