We bought some rural property about 25 years ago. About ten years ago we decided to build a large garage with a one bedroom apartment attached. We originally were thinking of pole barn construction, but finally decided on conventional stud construction with a crawl space beneath the apartment.
The footprint of the building is 36' x 64'. Our builder talked us into using attic trusses. The thought was that the attic trusses wouldn't add much to the cost, and would allow for cheap expansion in the future--if we ever wanted it. We ended up having the second floor finished while our garage/apartment was being built.
About half the first level is garage and the other half is living space in an "interlocking L" design. The living area had to be "L" shaped in order for all the rooms to be on an outside wall and have windows. We use the smaller open section of the garage as a big mud/laundry room. (It has a washer, dryer, laundry sink, freezer and has the rough plumbing for a toilet in case we ever want to add one.)
What we have suits our needs and after ten years we still love it. The downside is that there was a lot of cost escalation as the construction progressed, and potential resale value will suffer greatly because of the unusual design.
When it comes to recommendations for others, I think that you will be happy with about anything --- if you feel that you are maintaining or improving your standard of living. Our "city" home was a 1920's house with 9' ceilings, fairly large rooms, and lots of windows. We had our rural apartment built with 9' ceilings, fairly large rooms, and lots of windows. Since it was only going to be a weekend/vacation place we originally considered going the cheap route with baseboard heat, window air conditioners, bottom line cabinets, and cheap everything else. As the construction progressed, we realized we were going to be a lot happier with central HVAC, custom cabinets, upgraded woodwork and floor coverings, etc.
Ten years later we don't regret spending the extra money up front.
If you are considering going ahead, plan ahead for the sizing and location of your utilities, driveway, sewer/septic, etc. I eventually decided to have a pole barn built for additional storage. If I had anticipated this pole barn when I originally built my garage/apartment, I would have given a lot more thought to the location of my building, driveway, water line and buried electric line as well as the size of electric service I had installed.