Construction / Renovation on Kitchen and bath

I paid a contractor to install a wheelchair accessible bathroom so that my dad could come home from a nursing home. Inadvertently, they used most of the kitchen to put in the bathroom. They were also going to put an extension onto the kitchen. However, when the bathroom was finished, they asked for the money to do the kitchen. I paid them and they never returned. Now I have no money left to extend the kitchen, the bathroom drains do not work. We have 70 square feet left of our kitchen and I don't know what to do. I am hoping someone on here will see this and be willing to help.