Hi and welcome to yorkie talk!! It's a great place!
I've heard lots of different answers on the bathing question. Some people every 3 days, some once a week, some once every 2 weeks. I bathe my Hercules about every 2 - 3 weeks. I really think it's best to gauge how often you think Nikko needs to be bathed - like it might depend on how often he goes outside.
Please post pictures if you can!