Having a custom drawn designed house means a professional architect applies his skills limited to the individual homeowner's needs or what they have in mind. Factors considered in such a situation are the size of the site of construction, ideas of the individual homeowner, population around the area, and the nationally and locally existing building code plans. Time is also a considerable factor for completion of a custom designed house.
Some small homes have two floors and come with or without a basement. Some more common small homes have crawlspaces for extra storage. Traditionally they have a room off the kitchen which you can place a washer and dryer. These house are frequently Cottage or Bungalow style.
Getting a house plan made specifically for your requirements is a time-consuming process, and it also involves a lot of effort and cost. Online ones will enable you to cut short these inputs and you can get the design for your dream home incorporating any changes that you need in the shortest possible time. Building your house is a once-in-a-lifetime opportunity that must be done with utmost care and you must make an effort to incorporate all that you would like to have in your dream home, subject to availability of funds.
Remember that plans are not necessarily "as is." Builders can use a reverse set of plans (sometimes called a mirror image) to better site a house. It's also possible to hire an architect or modification service to personalize a plan. Ask if reproducible prints or electronic CADD files are available for the selected plan. Either will make the alteration process quicker and easier.