Need to get my office floor skimmed before laminating the floor as the concrete base is awful!! Looks like its been bodged fairly recently before I moved in. Probably only needs a skim. How hard is it to do DIY or is it something that should be left for a pro? I've seen some self levelling stuff you can buy but never used it before?

Any ideas?! (area is about 9sq. metres)

Cheers
Chris