If you mean stealth, then you can have as many as you like. But it will create suspicion and if one goes down, they all will. Stick to one account per address.
If you mean in general, then eBay allow one account per person. So would depend on how many live at that address. Again there will be links between the accounts, so not advisable.
Question is not clear. They allow 2 accts per person linked to 1 pp. so multiply by people in household. If your talking stealth then 1 is best practice.