No la, dont call yourself blur queen as everyone has to start some where. We are all sharing our individual experiences here only and views are often subjective.
So far I am able to re-use my mattresses for subsequent tenancies, as I always provide them with new mattress protectors and my mattresses usually come back with me clean and look almost new (except for 1 occassion). But i must qualify that I usually buy above avg mattresses such that they do not sag much over time.
As for those other damages, it really depends whether you want to close one eye, both eyes or none, lol. I will usually assess the overall condition of the house before deciding whether to charge them for the damages. If the overall condition of the unit is good, I will just refund them the full deposit even though there may be some minor damages or missing items. Otherwise, if you conclude that the tenant has not been taking decent care of your unit, you can charge them accordingly. There should be standard/market rates for certain items (eg. Changing of light bulbs, the cost of each bulb, labour + transport cost). For some other damages like scratches on parquet floor, funitures etc, although you can typically engage a handy man to do some rectification works (through grinding, polishing and re-coating), I would usually not proceed and ask for monetary compensation equivalent to the charge of the restoration works.
Corporate tenancy could be a little more tricky as they would usually ask for official invoices/receipts for the restoration works. Personal lease is more direct and straight forward, although the likelihood of them barganining / negotiating with you is much higher.
GOod luck, anything can PM me