Happy Hounds for Life: I need a database programmer

We are a young business offering online training to dog owners and CPD training to vets and vet nurses. We are looking for our website to be built that will be able to have 3/4 separate secure login areas for 1. Vets (with user permissions possible) 2. Dog Owners (to access dog training videos) 3. Staff from the Vets (to access CPD training) and 4. Animal charities (to access dog training materials). Within these secure areas they will be able to access all of our training videos (which may need to be hosted on a separate server). We are licensing our business so the vets will join our membership scheme to access both the training to give to their dog/puppy owners and CPD training for their staff so they need to be able to become a member through the website too. I have someone who can draw up a full technical spec of the database and everything that is needed but just looking for a rough figure so we know if this is a way we can get started and also how long something like this takes to build.
Thanks so much :)
Rachel