Help Júlia with a plumber's skills: a burst pipe behind the wall

In March an inspector told me that my home has a burst pipe behind the wall. It's a safety risk for me and my two small children. The landlord has refused to act, and quotes of $310 are beyond us. I'm looking for a licensed plumber who may be able to donate a few hours or do the repair at cost. I can cover the parts, which I estimate at $75. The job should take about eight hours. I'll make sure someone is home and will provide refreshments. I can share the inspector's written report on request. If you're a plumber and can help, or know a program that assists with this sort of repair, I'd really appreciate it. I never thought I'd be the one asking, and I'm grateful for every bit of support.