I paid a lot for having my floor put down, but I needed the guy to chisel away bits of concrete here and there and put a special damp sealant on the floor and then put a plastic damp proof course down and even the floor out with levelling compound and then even it out hightwise as there was a 2cm difference from one end to the other - he did that with chipboard - so lots of work involved. And there were pipes running across the room that needed to be avoided.... The room was about 25m2 and he charged me 1500 Euros. Worth every penny, he did a brilliant job in under a week and it looks fabulous. But I think my floor was a major challenge! So it all depends on what needs to be done and what type of flooring, mine was solid oak by the way.