Which woman had a small upstairs room made for Elisha?

Answer: A woman of Shunem

A prominent woman of Shunem asked her husband to make a small upstairs room with a bed, table, chair and lamp for Elisha.

“One day Elisha went to Shunem, and a prominent woman who lived there persuaded him to have a meal. So whenever he would pass by, he would stop there to eat.”— 2 Kings 4:8 (BSB)