Congratulations on getting a new Hav puppy! It's very exciting, and nerve-whracking. My Ricky is all black and his tears are easily removed when they dry out. I just lightly use my fingernail and it's all gone. No smell, no leaks, nothing.
Sammy has a lighter black/gray around his eyes so you see the 'crud' more, but again, it's not really a stain, just something I pick off every time I groom them. That was one of the main reasons I didn't want a light, sable pup, though I'd likely not care about that anymore.
What you want to know is whether the pup's parents are health-tested. There are soooooo many threads here about what to look out for, but I can steer you to the "Ask a Breeder forum": http://www.havaneseforum.com/forumdisplay.php?f=43
and you can click on the threads that interest you.
If you go here: http://www.havaneseforum.com/forums.php
under "forums", you'll see the list of different forums we have here and you're best bet is to check out the "puppy area" for great info on bringing baby home.
Have you checked the HCA website for a list of their breeder referrals? http://www.havanese.org/
Then, there's the OFA site where you can see if the pup's parents are listed. http://offa.org/index.html
Hope that helps you get off on the right track!