I have done this with no problems whatsoever - the lady we homed to was completely blind and she copes brilliantly with support staff around if she needs it though she cares for her dog, cat and her reptiles by herself and all are immaculate. They all see vet when needed and Cleo wears a collar with bell but aside from that in most cases the lady knows where she is as cleo is quite talkative.
one thing this lady did say to me was that she had thought about it very fully for around a year and whilst she understood that they can get underfoot she kinda shuffles round the house anyway. cleo and her dog jess get on brilliantly well and the whole thing has worked out very well .
I don't see any problem in such circumstances so long as the person has considered everything fully.
We have had quite a few similar cases but with say amputees, mental health, etc as other rescues round here can be very small minded about such things - their loss our gain!
Give the lady a chance I'd say - you may be surprised.