Start discussing with an Oak Park architect concerning the matter of providing you with a preliminary design plan suitable to your project, once you have the correct details about your project. A good architect will at first take all the data regarding the plans that you desire to employ in your development project and then he'll also assure whether you like the design or not and he will provide you the design of the project. Through first design plan you'll even be in a position to plan the budget for your project. However the budget may keep varying because the design changes. But at the least you will get the notion of the budget and then take other steps related to your project accordingly.