I think your cost is missing a zero.

But seriously, I think you'll need to throw some science at your customer. On a 22' diagonal screen your Epson at a bare minimum would have to be 29' away. On a 1.0 gain screen it would only produce about 10 fL. With even a bit of ambient light you'll need to produce at least 20 fL but more than likely 40-60 fL.

I've done 13' screens in ambient light where 12,000 lumens wasn't enough.