Shed concrete floor

[knobstop]

Hi guys newbee here
I moved into a property a year ago that in the garden had a 10 by 20ft concrete base which just had a garage removed from it as it was aspestos.
Anyway a build a shed ontop and painted the floor with floor paint.
I wish I had done my research as now the paint is all coming up.
Now I know whatever I do I've now got to get on my hands and knees and scrape the paint off.
The problem is that the concrete is a foot high in places ( slight slope in garden) and I don't think anyone used any damp layer underneath, I can't be sure as I didn't lay it but in the winter the floor does get ever so slightly damp.
The floor is a bit dusty also which I know I need to remove as much as possible.
Now what I'm after as cheap as possible is to try to seal the floor\damp proof and then paint on top so it sticks.
I thought I would pva it then paint it but have been told this won't work as PVA didn't like outdoors?
Now I've stumbled across cementone SBR on screwfix website, will this work?
If so how does it come and how do I use it?
Can it be painted over?
Thank you for reading

 

[noseall]

Why the urgency to have a posh floor in a shed?

I would look at other ways of achieving a smooth finish like floor tiles or a material covering.

 

[knobstop]

I never said there was an urgent rush nor did i say i wanted a posh floor.
plus surley tiles are more posh than paint!
Im using paint as the floor is very uneven and dont want to spend that much money, as in my original post ive said im trying to do this as cheap as possible.