We have 1 lady that does the piecing at our church. Although, I think her daughter helps make tops occassionaly. I know others have offered to do piecing but this seems to be her calling. She says she receives donated fabrics of all types from those who know she quilts. I don't know if she buys the batting. She brings the tops and backs to church once a month and a ladies circle in the church helps tie the quilts together. I believe most of our quilts are donated through our church Synod which sends them overseas.
She also makes quilts for all the high school seniors each year to have a quilt from the church to take to college.
We use a small SS classroom with tables setup to assemble the quilts and store quilting items. You may want to see if your church has space available that can be dedicated to quilting so you could lock the room.