Karen, In most cases I've seen for 17's you'll need 2 boxes which usually will be about 48-50 sq ft. Your Boler can't be too much different from the Casita which took right at 38 sq ft. Most places will let you return as long as the box is not open. If you get 2 boxes or about 50 sq ft you should have more than enough. As Raymond said, measure in squares then add 10-15% and you should have plenty
I don't know how much difference it might make at floor level, but the 17' Boler is significantly wider (maybe 10") than the 17' Casita
. If the Casita 17' took 38 sq ft, then adding another ten as Bill suggests sounds good to me.
I have put in this type of flooring in the house, and waste depends on your layout and the specific floor shape - it's not a big deal in a large room, but could be significant in a trailer-sized space.