And the carpet thickness must be less than 3mm, otherwise the laminate flooring is easy towarp when people walk on it as the flooring will sink and change too much when people step on it and the carpet is too thick.

If the thickness between the old and new is an issue, slight shims where replaced resolves that quickly.The dips or waves in the roof (ext picture) are generally from the rafters that are uneven across the span. 

I am thick skinned

I now provide pre-cut thick plastic washable shelf liners and actually have a clause in my lease about damage to cabinets -- no nails, push pins, other sharp objects (I've had tenants hang pictures with pushpins on side kitchen cabinets, screwed in hooks to hang things) and that stains and damage to cabinetry will not be considered normal wear and tear.   

Yup that's right it was 3 inches thick of flooring...before you even got to the sub floor.

Standard T-111 siding is about 5/8" thick and is made from plywood.  

I am literally in the thick of this right now.

At some places the cracks are a quarter inch thick.  

Hardwood & Thick laminate is too pricey.

Looks quite nice, old fashioned, but with up to 1/4 inch thick swirls.