Well for space my limit is 3 dogs, 2 cats and a fish (though I'm sure I could care for more fish!)
If I lived in the country and have lots of land I would probably get another dog and another cat at least. I don't worry about having enough time cause I'm almost always home and I never run out of love! One may get more attention today, but the others will get it tomorrow. It all works out. The girls have no problem asking for attention when they need it. Finn doesn't really so I make it a point to love on him.
So I guess I would say 3 or 4 depending on the dogs. If they are really independant you could probably have more, but if they're needy then only 3.
Vicki