Buying Tile Adhesive and Grout

I am looking for tile adhesive and grout that is compatible with underfloor heating

Is it more economical to buy grout seperately - say in hardware store rather than buying it with the tiles at the local tile shop?

Does anyone have any advise on the different qualities of grout that are available out there ?

There is some discussion on this topic in this previous thread. Your tiler may be able to avail of trade discount as mentioned here.

For ordinary grout in tiles I think I have read on AAM in the past that it is cheaper to buy from places like Woodies etc. because the tile shops charge a lot more. A read through some of the previous threads in this forum may confirm this.

Flexible floor adhesive. I buy it at House of Tiles all the time as I find that they are good value.

Also would go for grey flexible grout as floors get very dirty and the ivory or white grout dont clean off too good after a while.