Thanks for your help
Sorry but tl;dr. However, the most you can charge for in any case is the loss in value of the item beyond fair wear and tear. Therefore you have to know the original cost, (C), its current age (A), the expected life of the item, (L) and its value in its current state, (V). The claim would then be:
C x (L - A) - V
Alternatively, you can claim the actual cost of disposal, cleaning or repair if this is feasible.
My guess is you wouldn’t get much for the mattress, lightbulbs would probably be wear and tear, nothing for the shower as you would have been expected to spot it during routine inspections.
Needless to say, if they dispute it, you need excellent evidence of each, including before and after photos and a description of the condition of each item on entry signed by the tenant.
Thank you for you response.