I’m working on a new design so things are fluid. It’s a ‘cottage/seasonal home’. 

Home is on a slab so no basement or crawl space. Main is about 1,000 square feet and upper (1-1/2 story to 60” side walls) is about 350. I have room upstairs at the top of stairs for a small utility closet. It’s 38” x 66” with a 32” or wider door facing a 66” square landing. It is however, under the eaves. 8’ High front (door) and 60” in back. Plenty of room for a tankless water heater. I hope to use tankless for radiant floor heating. This is stacked above a roughly 6’x8’ laundry on main level.

Detached garage will be 30 to 40 feet away (even in MN … do NOT want attached garage).

opinion on splitting utilities to different spaces. Also want water softener and will need a pump (not on city water).

thanks,
John