What next

[Scenestra]

My elderly roommate has a small dog I seem to have inherited. She's a Pom/Poodle about 4 lb. she was severely mistreated when she was younger. My RM won't discipline the dog at all for fear of making her worse. Luckily she only has one terribly problematic behavior, because she is so nervous she's a barker. She barks at the neighbors, the cars on the road, from in the house. I have been working with her, but her fear interferes with her food drive so treats are only mildly effective motivation, the clicker scares the crud out of her etc... We finally got it so she will come up and take a treat from your hand but very cautiously. I would like to start to teach her normal commands like sit and stay but if you reach over her she either bolts not to be scene for hours or roles over in submission. So holding a treat in one hand calling sit and touching her rear is not going to work. I'm the only one in the house she trusts enough to even take a treat from everyone else pretty much has to either toss it out to her, which also scares her, or set it down and back away. Does anyone have any ideas on what to possibly try next?