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TLDR: concrete pad, shed base, floor, vapour/ moisture barrier(s) goes where?

Hi All,
I am building a large (10x15) shed/office in the garden and I am slightly confused about the floor vapour/ moisture barrier, looked everywhere online and want to clarify the following.

Sub floor - old broken concrete base put in by previous tenant (I think they had a car port there)
Levelled out by ballast & sand
Layer of polythene vapour barrier
100mm concrete base
Shed base (treated batons running the length of the shed)
Shed floor (15mm shiplap running counter to the batons under)

My question is, do I need a vapour/ moisture barrier anywhere between the concrete pad and the shed floor that I physically walk on? And if so.. what/ where?
It comes raised on batons and I plan on both heating and insulating the rest of the shed with basic insulation (it won’t be a living space)

Ultimately I want to insulate the floor from the inside before putting some kind of laminate/ office carpet panels on top, not sure if that makes a difference
Thanks in advance

I would lay the floor bearers to the concrete base on a strip of damp course, which is quite cheap for a roll at Screwfix. You could make a floating floor on the shed floor with an insulation slab with a chipboard floor over to give an even substrate for your laminate (I would use vinyl) Just check your door threshold can cope with the thicker floor section.

DWD