I've been known to take my three out together on leash. It's really not too bad. For one thing, I put Bimmer on the longest lead and he won't let the grrrrls get out of line, plus they are used to following his lead. Everyone should have a Bimmer-dog
Try the lady here, oriondw, who has THIRTEEN Saint Bernards. I've never seen her take all of them out in public, they won't all fit in her van, but on any given day she'll have 6 or 7 with her. Well over 1,000lbs of dog! LOL!
My sister has nine dogs but they range in size from large to teensy...her largest is I think her lab and her pointer...smallest is her corgi and her boston.
WOW I always wonder how Renee, Barb, etc... do it. My largest dog is Precious, at a whopping 50lbs. I absolutely love big dogs, I mean there is so much more to hug. But, I could not handle more than 2 (if that many!) large dogs.