If you are using a removalist company, it is really important that you check for damage to your items as they bring them in. It is no use finding damage to your stuff a month after you have moved, as you have no way of proving that it was caused by the removalists.
This is when you also need to check for missing items. Most removalists will make you sign an inventory form, where you check off that all of your items have been transported from your old place to your new one. If your friends are helping you out and you find that there are items missing or that stuff has been damaged, there isn’t anything you can do about it.
In most cases you won’t be covered by moving insurance, and it’s not as if you can blame your friends for it—they were doing you a favour. This is just one of the risks that you take when you don’t use a removalist company.