Inventory Format

I am using OpenRent to create the tenancy.

Is there any inventory format?
Can the landlord take the photographs and prepare the inventory then both landlord and tenant sign the inventory?

Does it need to be done by any professional?

The landlord can prepare the inventory themselves and the photos and they can also do the check-in/check-out inspections. The level of detail has to be high. My inventory for a one bed flat runs to 6 pages.