I'm with Ruth on the companionship of a pet, I won't ever be without a dog or a cat in my home, especially if I lived alone. I agree with her that it's something that needs to be thought about a lot beforehand. If you're physically able to walk the dog at least three times a day, I think I remember you saying that you might use a cane in the house and don't walk as fast and securely as you used to.
Also, there's a lot of work taking care of the dog, daily feedings, water changes, grooming, cleaning up after their messes, even if it's muddy paw prints on floors and furniture. If it's an older dog that's reliably house trained, it will be a lot easier for you. Also, whenever they go potty outside, you have to pick it up with a little plastic baggie.
I understand that some people with very small dogs use a litter box for them, like they do with cats. Just in case they have to go and you can't take them out. If you're ever gone for a few days or a week, someone will have to doggie-sit for you in your absence. Also, some small dogs are yippers or barkers, don't know if that's an issue in your building.
There's great rewards having a loving pet, but lots of extra work too. If you're up to it, you should go for it Lon, I know you'll make the right decision.
