If you want to DIY one it should include
Smoke, Heat, CO alarms, are they still in place and do they respond to the test buttons
Meter readings
Exterior: Comments on decor, guttering, garden, fences etc
Interior: Lack(?) of water leaks/damage inside all rooms; any decoration / mainteance issues. Mentions any/all little niggles you may have even if you have already reported them.
State that you have no additional tenants, unauthorised cats, dogs etc and don't smoke in the property
Pictures need only be one or two wide angles per room. Nothing inside cupboards etc. Be kind, show them the inside of the clean hob/oven and shower cubicle.
Any clerk who uses an App to do their reports should be able to send you/the agents a blank report for you to complete. And you never know, they may be pleased that you suggest a DIY version! Depends on your agent/landlord!