Boo is 10 lbs, Gracie nearly 4 and Yogi nearly 3. Gracie may put on another pound, Yogi a couple. The bones are a bit more fragile, and you do have to be more aware of them while they are young because they don't understand about heights. But they aren't like eggs, they'll take a certain amount of "abuse" and won't break. My DH, on the other hand, has nearly broken his neck several times trying to avoid them because he didn't look before he took a step.
You'd think it would be easier to train the man to look first-step second, then to train the puppy to stay out of Daddy's way.
But no, I've been trying to teach him that for 7 years.
Yogi has a bell on his collar that helps DH to know where he is. All three have been 'punted'.
Nothing serious, but it taught them to stay back from Daddy...who is still trying to learn to look first-step second.
We have a step stool that G uses to get up and down from the couch. She'll run from one end to the other to use the steps instead of jumping off. Yogi is too young and the whole jumping up/down still intimates him.
If you'd like a smaller one, go for it. Get a bell for it's collar, look first-step second. Use a little common sense while it's growing and learning. The most important thing is that you and the puppy connect.