x2 what Dytecture said, this is not enough to go on. Most important thing before you do anything, is you need to know lot restrictions in that area and what are the zoning requirements, i.e. side, rear,front, set-backs. In addition the size of your house will also depend on the total percentage of a lot that can be covered by impervious surfaces (structures, decks, and surfaces likes asphalt or concrete driveways etc, which reduce natural infiltration, etc and after you obtain that information, only then you can contact a local Architect and you can roughly come up with the size of your house and layout on the lot... until that, the information you get here it will be useless to you in your case and a waste of time for everyone else. With that said, 40x104 is not a confirming lot for most of the area around here and you will need variances because confirming lot sizes usually start at 50x100, unless you in a section where ordinances permit residential cluster development. Good luck.

A rule of thumb is that the distance between the house and a eucalyptus should be 2/3 the height of the tree. So if the tree is maybe 45 feet, you'd want the house to be a little over 29 feet away. As well as any new root growth that could affect your house, cutting into a root system compromises the stability of the tree. Also, even if the existing roots are deep, driving over the area with heavy construction machinery could compact the soil enough to affect the health of the tree. That's not to say that you shouldn't try, just be aware in case it becomes necessary to cut the tree down later. Good luck and enjoy your new home!

Hello Pawan, for a complete map of your house you must share complete details. We can provide the layout with complete details. You can contact us for the same.

send all side photos ( inside & outside ) also, to visualised each walls what is obstructing outside