Why: No available home offered the amenities that I wanted. Home architecture seems to focus on increasingly elaborate variations on the 3 bedroom 2 bath conventional home at higher and higher densities.
How: After designing a home following "A Pattern language" by Christopher Alexander and taking a course in owner-built homes multiple times, I got a construction loan at an exorbitant rate from private money (brokered by a specialist in private money). Then, I served as my own general contractor using conventional project management methods. Once the house was finished, it was easy to get a conventional home mortgage.