Yay! Another Kansan!
Welcome to Yorkie Talk. I'm sure you'll get lots of help with all your questions here.
Definitely get a harness - their little necks are very delicate.
Fang and Errol developed something similar to kennel cough at about 14 weeks old - it took 3 or 4 rounds of antibiotics and about 4 months before they finally stopped coughing.
We try not to go more than 8 or 9 hours without potty breaks. We crate them during the day when we're at work (they go 4-5 hours in there with a mid-day break when I'm home for lunch), and when we are asleep overnight (that's the 8-9 hour time). The rest of the time they have constant access to the bathroom. They were able to hold it 4-5 hours at 12 weeks old, but they were closer to 5 or 6 months old before they could hold it all night.
