I would start by working out what functional things you anticipate you need. Websites are wonderful but can often get bloated by customers throwing in every option they can think of. You need to decide why you want a website and who it is designed for. There is a big difference between a website running an online campaign and a small business website who just wants people to be able to find them online.
Separate out what functional things you anticipate versus the design elements. You sound like you have a design in mind but without knowing more about the website making process your design ideas may be flawed. Website can mostly be 'wireframed' by using different tools that put sample artwork or boxes as placeholders to layout a page. These don't need to be complicated and you could use a pen and paper to achieve this without needing to draw things up on a computer. You'd be surprised how plain a lot of websites look when you break them down to Header, Navigation, Content area, Sidebar, Footer. Add a few interest areas and suddenly website all start to look the same.
If you have a design that you don't want others to 'steal' and it is a truly novel idea then seeking out a designer with a generic wireframe and a list of the 6 pages you anticipate needing, a few forms, gallery and a slider will give them a much better place to start the conversation and think about pricing.