We are in the process of filling our gaps with pine slithers (they cam in different widths) You can buy them online. You do suffer from bald/ red knees when you hammer them in and then need to chisel them down so they are flush with the rest of the floor but it really does help. What you can also order with the pine slithers is pine saw dust with resin - you mix the two up and can fill the really narrow gaps which the slithers don't fit into. If you don't mind spending the time doing this I would recommend it yourself (especially if you're worried about costs), depending how big the surface is, and then have someone in to do the sanding. The varnishing you can also do you yourself with a normal paint roller. We also recently had a quote for sanding and varnishing and I think it came to £500 for mid size living room and 3 m length hall.

I know exactly how you feel. I had a similar situation. The prospect of lifting the board and potentially raising the level made me wait. The wood darkened, and now I'm never fully sure where that board is. In fact, I forgot all about it till I saw this post. Wait a while. If it still bothers you in six months or a year maybe then consider lifting it. But I guarantee you won't, lol!

Bathroom tiles gold and black I need to introduce another colour???

I would appreciate some help with an upstairs floor plan. This is the current layout but it’s resulting in Bedroom 2 and Bedroom 3 having really small windows due to the pitch in the roof of the single story part of the house below… best views are south of the floor plan so we are trying to maximise windows. Thoughts or alternative layouts would be much appreciated. Everything is up for grabs, the only thing can’t really change drastically is location of stairs.