My dad owns an upholstery shop. He pretty much provides furniture with padding, springs, and fabric covers.
I would love to work with your dad to learn how to upholster furniture.  Recycling furniture is a growing market
It really is. Uphosterers, or trimmers as they are sometimes called, can always find business. People always need them.
It seems like I run into someone daily getting a sofa or dinning room chairs upholstered. Do you ever help him?
Sometimes I help him with the simple stuff, like seats. I'll help with the padding and cover them with either leather or just regular fabric