What is the question?

Build as if you are going to live there forever, but able to sell it tomorrow. Engaging a local architect will help.

A small 2-bedroom house with a second floor loft is probably a misfit. A loft will require a stair, which will take up room on the first floor, but only leading to an open space loft on the upper level. Is there a special reason for wanting a loft?

It might be simpler and less expensive to simply build a 3 BR 2 B one-level house, depending on design.

Good luck on your project.

I'd ask Houzz, politely, to remove this post. You've posted your name and address on a very public forum! :(