I have a friend with a Havanese that is a wonderful dog. We also are very close with our neighbor's Shih-Tzu (as in - he often spends the night on our couch). He's a really great pup.
Personally, our dogs have always been mixes from shelters (always puppies, though, just personal preference) and we've always had big dogs, but we are thinking of adopting a 3rd dog of a smaller breed in the next year or two, most likely an adult or older dog.
Quick story: My brother adopted an adult Rottie mix from a shelter many years ago and had a heck of a time with him. Because he was new, my brother wouldn't leave him alone without confinement. Unfortunately the dog would tear his own face off in order to escape the crate (and succeeded many times, leaving a bloody trail across the new carpet and pricey vet bills in his wake).
So then my brother tried taking him with him when he had to run errands. Result was chewed up steering wheel, chewed up shift knob, sunglasses, cell phone...
So next he thought it'd be smart to lock him in a bedroom when he had to go out. By now the dog was on anti-anxiety drugs from the vet. BIG mistake. Goodbye door, goodbye carpet (apparently the medication gave poor "Murray" projectile diarrhea, so goodbye doggie prozac too).
At his wits end, my brother spent thousands to have the backyard patio poured so that he could leave the dog out there. OH LORD, that was the worst of them all! Murray very skillfully pulled every screen off every rear facing door and window, mangled them, and piled them up in a heap on the patio (saw it with my own eyes!) After that, he dug holes and my brother found him 3 houses down in the neighbor's backyard, still trying to dig his way out!
SIGH. So my brother calls me in tears, because when he's home the dog is perfect, but he can't figure out what to do with him. He's ready to admit to himself that Murry might have to go back to the shelter, which is tearing him up because he thinks this damn dog will never find a family given his behavioral problems and separation anxiety.
Later, my bro has to leave the house and decides to heck with it. For Murray's own safety he just left him in the house, free reign, expecting the worst (was planning to return him to the shelter the next day). What does he find when he comes home? Murray sitting on his pillow, smiling at him, not one object out of place, no accidents, no chewing, no destruction...Murray behaved like a perfect gentleman.
LOL, apparently he was simply offended by the lack of trust
My brother still has Murray to this day, even though I attempted to steal him many times because he's such a wonderful dog!
I don't really have a point with that story, just thought it fitting. Rescues can be very demanding but also very rewarding.