I'm with Paddyboy99. I never tried it before and with some guidance, I've done a pretty good job. For the first floor I used a homemade set of levers/short planks to wedge the glued planks together. I glued 4 planks, then let them dry while i did 4 more in the adjacant room, and so on. Then I got ratchet clamps in a diy store in France for €8 each - they cost €25-30 here. Made the job a doddle for one man. I used evostick wood glue (1 green bottle is nearly enough for a room). Remove skirting and clean the floor. Lay out the underflooring. The standard white cheap one is ok for most floors - and cheap. A man "in the know" suggested I should have also put down sheets of newspaper/ wallpaper to improve sound proofing.My problem was the cheap all-in-one door frames the builders used. You could floor up to the door and get a premade edge to finish the look. I removed the door frame and raised the whole lot so the boards went under the frame. It's a lot of bother but looks good. I wouldn't have done it unless DIY expert dad in law showed me.
Have a go. The varnishing is the worst bit!