Landlord wants to take Mattress Protector costs amongst others...

greensalad

Went through similar with petty landlord. 

Take it to tribunal. Be reasonable. Raise evidence against each point you wish to counter. 

For example:

I got a claim for a charge of £180 for cleaning, despite having had a professional End of Tenancy clean done. Reasons were that:

- dishwasher sides were greasy
- washing machine drawer was dirty
- extractor fan in bathroom had dust on it

These small areas had been missed by both me and the end of tenancy cleaner. I stated that £180 was not a reasonable cost to charge for these small areas, and counteracted each point. Dishwasher I was able to evidence that it had been noted to be less than satisfactory in the check-in inventory. Washing machine drawer and extractor fan were true, and I did not contest that they were dirty but instead offered to pay what I felt was a reasonable cost. I think I stated that both items could be cleaned in 1hr and local rate was £12.50 therefore I offered them to withhold £12.50 from my deposit, I won and was deducted £12.50 instead of £180.

In your case I would ask for a list of all areas that were not clean, and ask for evidence (e.g photographs or external check-out inventory which should note these). If they cannot provide proof they won't be able to claim from you. If they can provide proof, then you can do as above and offer a reasonable amount. 

For mattress protectors I would say the same, wear and tear. If they won't budge go to tribunal.