1) there's gonna be at least 4 people there. Me, Solscud, phatslappy and phatslappy's stalker. He'll be there way before anyone else.
2) You can bring stuff to sell but you're responsible for watching it yourself. No one is liable for anyone's stuff. People at the con are really good about respecting other's people's stuff there, I haven't heard of any incidents where someone disrespects anything that didn't belong to them, but that doesn't mean you can be irresponsible.
3. No entrance fee. You might want to bring money for food and the MWCon Tshirt. And there will be people hawking their stuff.