Welcome to the Forum, Jean.
I think your business idea is great. The ceilings look great and I'm sure you should make lots of sales.
I hope I won't offend you, but let me give you a bit of feedback (which you didn't ask for and 'Help is defined by the Recipient
'). When I hear Tin Ceilings, I instinctively think 'cheap'. Yet the effects you create are astounding. I wonder whether you're being too honest here. I might express it as being too product-driven rather than customer-centric. You're selling the final effect. How you get there could be your secret?
Perhaps I've given enough to suggest one person's reaction. If I'm going down a path you've explored already, well have a nice day anyway.