This one is related to the first, but even experienced developers can fall into this trap. There's a diverse range of expertise that goes into building a website. This includes photography, graphic design, database management, an understanding of information architecture, business and time management, web programming and content writing.

Many web developers will tell you they can do what you want, even if they can't. Maybe they're hoping they'll be able to figure it out after they get the job, that they can just take a quick photograph and it'll look fine, or that designing your logo will only take a few minutes. They may be an expert programmer, but that doesn't mean they've got good aesthetic taste. When someone agrees to do work they aren't experienced at, the finished product is a shoddy-looking website.

Many web development companies to sell you all sorts of additional functions, for a lot of money. Many of these can be useful in the right context, but many of them more time and money for them, what to do. If the function requires ongoing maintenance and input, even long after your site is to ask yourself that, if its really in your budget.