In article , N.
Thornton writes

How big is big enough to be of value? 50 sq ft? 60 sq ft? Even smaller?

Regards, NT

I would think the shape mattered as well, a 5foot wide corridor type
space would be much less useful than a bed width, or length
--
Janet Tweedy
Dalmatian Telegraph
http://www.lancedal.demon.co.uk