We also worked with one for our custom home. We started by finding who designed homes in our area we liked. We wanted a very specific style. In the first meeting you can ask to see the portfolio and have them outline what they will do for you and what it will cost. They will give you an initial cost and then costs for changes. Changes, once the plans are done, are very expensive so it is best to come in with a good idea of what you'd like. The architect also may do a very rough draft of what is possible on the lot you are looking to build on. It helps to come with a survey or have them visit the site. You should not be charged for this meeting as this is the sales pitch meeting.
Once we picked our architect, we came up with a wish list for what we wanted. I think my list was 5 pages long! The more specific you can be the better. I had big things like large closets, number of bedrooms to really specific things like niches in all the bathrooms for holding shampoo. It helps to really think hard about the way you live and what you want. I also brought magazine or internet pictures of things I liked. Some of these things will be design elements done by the builder and some will be in the architectural plans.
After that meeting, he did a floor plan, budget and design elevation. It was very exciting to see our dream home come to life! Now it got hard for us. It is typical that to meet your initial dreams the home is bigger and more $$$ then you want to spend. So you start to make decisions about what you can cut and consolidate.(do we really need that many bathrooms??? Bathrooms are expensive) Once you agree on this, they do all the electrical and plumbing plans and anything else you may need to get builder bids and permits. They may help you with builder bidding and selection.
Once you start building, you may find things are not what you would thought they would be so you need to make changes. The architect works with you and the builder on this. As I said this is expensive so the more you get the plans right before you start the cheaper it will be.
I loved the whole process of working with the architect. They are very creative people! And I am beyond thrilled with our home.