Make sure you have food and drink for yourself if you're in it alone! I was so scared to go feed myself last weekend at mine, that I called a pizza to be delivered

Be prepared for a long day doing nothing, because there's no guarantee people will show up.

Have coinage as well as notes for change.

If your neighbours come for a stickybeak and say they'll pay you back as soon as they make sure [insert item here] is in working condition, don't trust them! I ended up getting paid (with a $100 note for $16 of stuff *sigh*) but only after chasing them up three days later