If the cost of professional movers seems too cost prohibitive for you, there are a few things to consider that might change your mind. First, you don't have to use professional movers for your whole move. Consider the way the movers charge, and then make a decision about where their services are most valuable to you.
Some movers charge by the hour, so you could make sure that they're at your home for no more than an hour or two, and just use them move the big pieces of furniture that are hard for you to manage. A bed, heavy bureau, large dining room table, or large TV are all things you don't want to move on your own. But you don't necessarily need to pay someone to move your boxes of clothes, books, and kitchen materials. You should be able to put them in a van yourself or you take a couple of trips in your car.
This also works with movers who charge by the number of boxes and items to be moved. There are a lot of space-consuming items that are really quite light and portable. If you fold up the comforter from your bed and add in your pillows and linens, those will take up a couple of large boxes. You don’t want to pay professional movers to move something that's easy to pack and move yourself.
Let the professionals take care of the difficult stuff, really heavy items, or valuable items that you want to have insured. The cost of renting a van yourself or taking a few car trips with the rest of your belongings will be much smaller--so if your time is more expendable than your income, use professional movers but use them wisely.