Finding the right web developer may play the biggest role in determining whether your project fails or succeeds. You know your business and your market? It is up to you to ensure that your overall plan is sound. A good developer will have experience with the technology you are looking for and can explain what will work and what will not work. A poor developer will simply build it without asking questions, and without any development feedback, you won’t know about problems until it is too late.
When you look for a developer, ask what the largest and most complex project that developer completed was. If the developer has done a site as large as or larger than what you are asking for, there is a good chance he knows what it will take to build your site. If he hasn’t, then you are taking on the risk of the having the developer push uncharted territory at your cost.