I got my mini smooth at 8 months old from his birth family, due to a terminal illness. He chewed shoes, his toilet training went into complete regression, he was terribly anxious, and still cannot be left alone for more than half an hour with a stuffed kong. I pay a fortune for dog daycare and have no social life.
He'll still nab slippers, socks and bras if given half a chance. He'll run off with anything that has a strong smell of human on it (my running gear!). He's a proper hound and digs. He buries treats. Then digs them up and brings them in the house.
I have a rescue collie and he's very jealous of him. He'll fly at his throat if he thinks he's getting too much attention/too close to his food bowl. The collie has never touched his food.
I never got the recall cracked but I did get 'stand!' and he'll stop dead and not move, so I can catch him. He does play fetch with a tiny ball but I think that's because the collie does and he's jealous, rather than any natural inclination!
He doesn't pee/poo in the house any more but it took a good year or two of constantly taking him out, well bribing him out with treats. Except he will pee in the kitchen in protest if I spend too long upstairs...I have a safety gate (they must not go upstairs, or rather down, because of their backs) and a ramp so he can get on the sofa without straining his back (just you try and keep them off the furniture, I dare you, you will fail).
If I was to do it again I would get two, they need another one I think. They love to be near you or near another dog and my collie (entirely reasonably) won't entertain him.
I think a rescue dog or older dog will have the toileting issues just for being moved. They are not bombproof at all in that area. In fact they are pissy little individuals, they just don't care. He will mark if I take him to my friends' houses, so I go equipped with Special Solution and a cloth and poo bags. I don't have many friends who ask me over!
All in all they're a bloody nightmare and I strongly recommend you don't get one! He's my loving little clown though, a huge soul, a wacky personality, he loves to play, (scent games, dog casino, wobblers with treats in), he loves a walk and can go for miles but NOT in the rain, he LOVES people visiting, he loves to go out with me on my bike (I have a front carrier with a harness for him).
But yeah, just don't get one.