hi Paul, sorry I haven't got back to you earlier, in regard to the adhesive there's a product on this site so if you google 'best way to remove adhesive from concrete' it will describe different ways on how to do it, it's a pain to do but it has to be done.
If you try and use sandpaper on a belt sander or drill attachment it will be useless, the sandpaper will lose all it's grit immediately.
What size are the tiles, but a 4 inch or 6 inch colt bit using a hammer can do it, usually the tiles will come off quite easily, they will break but that doesn't matter.
If the tiles are placed on cement sheeting you may want to pull up all the sheeting, normally on wooden floorboards, but then it's extra cost to install new sheeting, plus you will need a saw either handheld or an electric saw or a tool you can but which specifically cuts cement sheeting and/or hardiplank, if you prefer to get a handyman to do it for you, sometimes it makes your job easier.
The tiles can't be put straight onto the wooden floorboards, because they will crack as you walk on the boards.
Another option is to have polished floorboards, where you take up everything then get a floor sander to sand the whole floor and then lacquer them, probably about 3 coats.
In my kitchen, dining room, lounge room, hallway and spare den, I laid parquetry throughout, it wasn't cold on our feet and can always be resanded if need be, or perhaps a floating floor maybe your choice.
Let me know if ythis helps you. Geoff.
