Gene,
It all depends on what you want. If you only want the exterior walls, easy. If you want the interior too, that is more work on your part.
You basically have to send me a hand drawing of your house with certain dimensions on it. If you have a set of plans from the builder, just send me those. Otherwise, you need to measure the outside dimensions of your house; width, length, offsets; all window and door sizes and locations; pitch of the roof and pictures of all four sides. From this I can hopefully draw an N scale set of plans actual size that you can use as templates for building your own house out of styrene or wood. I would send you several sets to verify measurements before the final building plans were provided.
If you want the full interior too, I would need all the room dimensions for each floor and location of plumbing fixtures etc. I assume if you are going to do the interiors, you would want to do the stove, refg., tubs, etc. in their proper locations.
It sounds complicated, but I have been doing this for a long time. I'll hold your hand throughout the process and get you a set of full size plans you can build from. What's more is that I can also build it for you if you like. That's extra of course. Discount is provided for OG members. ;)
B-)