Visit various cemeteries and compare prices.
Ask what they charge for grave opening and closing.
Ask whether you are required to buy a vault (in NJ, you must purchase this from a funeral director).
In addition, you will likely want to buy a headstone. Ask if you can buy from any vendor and if the cemetery charges for installation, requires a base, etc.
Interesting Headstone Information The Definitive Guide to Choosing a Headstone
Keep in mind that cemetery charges are separate from what you will pay the funeral director.
Buy and Sell online: