Where should I put the Master Bed?

[N/A N/A]

I’m looking at a rehab and wondering the best place to put the master bed/bath. It has a huge lot, but putting it on the rear of the home is kind of weird but maybe the only place. You would have to walk through the kitchen and utility room to get to it. This is a 1 bed, 1 bath 630sq.ft. home. I’m thinking about making it a 1.5 and putting the master bed and possibly a bath upstairs. Is this a good idea?
What would yall suggest? Can most skilled contractors convert a 1 story to a 2 story?
Like I said, adding on to the back might be the only way to go.
2 bed 1 bath homes in this area are selling for $118,000+. It’s a very desirable area.