I would agree, thing is though they probly didnt due to how much space stairs would take up making the upstairs not really any more space... the house needs to be bigger on the inside vs whats outside

Or what they should really allow is outside adjustment to use more of the lot for the house... i'd trade more outside for inside area then stairs could fit and a 2nd floor viable... i mean the roof already has the elements so clearly someone was planning a 2nd floor for it at one point in the dev process