Coffee roasting - start up costs and advice

Having been ground down by the man, I want to start a side hustle I’m passionate about and am considering roasting my own coffee beans from my garage and selling them. 

I know a little bit about coffee but am a total beginner when it comes to roasting. What does a half decent small roaster (5 to 10kg) cost? And what are people’s experience of sourcing beans etc? 

This is just a pipe dream at the moment but I’m trying to assess its viability (without bankrupting myself).