Tish ditto what others said if you have timber floors. You can sand using a hand-held orbital sander (it sucks and is slow but it works well enough). I did 3 large sized bedrooms this way once, mum hand brushed 2 of the rooms with varnish (doubt it was "floor qaulity" and "whitewashed" the other with a light blue paint and then sealed it with varnish. The paint worked the best