Old brown tiles through out flat really need a lift what can I do?

what are the tiles made of? Are you considering painting?

Old ceramic tiles can develop a haze from years of cleaner and dirt buildup which results in dingy, dull-looking tiles that never look completely clean. Breathe new life into old tile instead of replacing it by removing years of grime and residue with proper cleaning. Proper cleaning scrubs away dirt without damaging the tile surface or weakening the old grout.

http://homeguides.sfgate.com/clean-old-tile-26172.html

You can paint them, as well, even using stencils. I really want to do this with my outdated tile in my foyer and half bath, and this blog is the one I love and will turn to for my tutorial:

http://remingtonavenue.com/2015/08/the-girl-who-painted-her-tile.html

Option 1. Clean the floors as thoroughly as you can and just paint the floors including the grout. Paint rooms different colors or all the same, probably using cement or enamel paint. You need lots of ventilation.

Option 2. Rip out all the tiles and start from scratch. Install laminate flooring by the roll that looks like stone or wood. This involves heavy glue so, again, ventilate!

Option 3. Take out all of the tile and smooth out any rough spots. Install real or manufactured wood flooring and ceramic tile in each room needed.

Best wishes on redecorating your flat. Post photos! 😇

If you like the tile then just paint the grout. I had beige color bath tile and painted the grout a shade beige lighter. Looks good

Thank you. Never thought of painting and since I hate the current colour looks like I will be painting tiles as well.