Before you order, it's a good idea to make a note of the following so you have it to hand.
What type of heating oil you need. How much oil you need.
How quickly you need an order.
The capacity of your oil tank.
What size of delivery tanker you need/if there any restrictions to access your property or the roads leading up to your property?
Whether you need to order for a domestic or commercial boiler.
A safe tank with no damage, that can be clearly inspected. If you have any specific special ordering criteria, such as offset fill, underground tank etc.