Apologies if anybody has said this already, but, OP is 50, not 70! She is the same age as many of our children and preoccupations with “future proofing” her life, home, location are really not relevant .
Live your life, pursue your dream, OP, time enough for the “sensible” bungalow on a bus route, the tartan shopping trolley and the beige mac and sensible shoes in another 30 years !
Do your research though and don’t commit to a lifestyle you may not be able to sustain. Animal rescue is not all fluffy puppies or sweet little donkeys- vets don’t come cheap, you need to know what you are doing and it’s also a 24/7 commitment.
You are very young to be a granny but get out there before you sink into knitting Shreddies and follow your dream!