Is this punctuated correctly??

Question

so now, when you have nowhere else to go, you come back to us

Answer 1

This is how I do it

So now; When you have no where else to go, you come back to us.

Yours is right but I would rather it this way because I have long separation after now  

Answer 2

yes

Answer 3

The commas are in the correct places, but maybe you need a capital S to begin the sentence (if it is to be a full sentence) and either a full stop or question mark at the end. If the person who speaks this is making a statement then it is  a full stop, if they are expecting a reply then you need the question mark .:-)