When to have parents/family visit new baby?

Melissa • Just tracking my period!
My husband and I live in California (so does my brother). Both sets of our parents live in Pennsylvania; they are all used to staying with us in our tiny 2bd/1ba house. We are, obviously, converting the extra bedroom to a nursery.
I'd love your opinion on when we should tell our parents to visit after the baby is born. I don't want them here together--it's just too much, even if they don't both stay with us--so how do we handle this? 
Also, how would you handle the expectation of staying in our home? 
Tricky stuff. Thanks for any advice! ?