Can I add castors to this? the kind that will raise the bed a few inches?

Hey SweetPea70 this is Brookside. Thanks for reaching out to us. No you cannot add castors to this bed frame as it already comes with them. Doing so would affect the height of the middle bar suspended from the ground and could cause the bar to bend. If you choose to add different castors please keep in mind that any damages to the frame will not be covered under warranty. If you have any other questions please reach out to us at info@brooksidehomedesigns.com Best, Brookside