The CERTIFICATE OF INSURANCE is very important - many buildings require it, especially high rises, co-ops or any building with a doorman. You MUST check with your building manager before your move to find out if you need a Certificate of Insurance, and if so fill it out. More info here
Use brown or clear packing tape, not masking tape, blue painter's tape, or duct tape, on your boxes. Masking tape just doesn't hold.
Pack everything in boxes. Garbage bags can split.
You don't want your boxes to be too heavy, but you don't want them to collapse either. A good strategy is combining books on bottom with bedding, towels, or pillows on top.
Especially for walk-up moves, please put heavy items like books in small boxes only. Boxes that are too heavy strain the crew, slowing down your move.
Make sure all your packing is done before your movers arrive. Everything will go much faster this way.
Group boxes together closest to the front door. They will be the first thing we move.
Lamps should be boxed, because the lampshades are delicate.
Don't be shy about asking to check the van at the end of your move to make double sure that there's nothing left behind. If anything was missed, we'll call you immediately.