What Toilet For Small Powder Room? In-wall or not?

Hi,
I am having a powder room built in our house which is undergoing renos. We are limited by interior space which will be 3'x5'. We can go slightly wider maybe 3.5' but the limiting factor is length where we can maybe go to 5'3" (interior) if we turn the studs sideways, play with the space... We will have the toilet and sink (small wash basin) face each other.

I am considering going with a Toto 26.5" depth toilet (27.5" off the wall realistically) with a 12" wash basin, which would leave about 20" in between toilet and sink.. Do you think this is enough?

I am also considering an in wall Toto or Duravit (I guess Gerberit system? need to research) to save space. What is the feedback? Would anyone recommend? Would I actually save that much space? Do they clog more? Is it hard to repair being in the wall?

Many Thanks for your input,
Chinstrap

There is often a building code requirement about room in front of both the toilet to an obstruction and a sink. At 20", I don't think you would meet either clearance requirement in some places. For the toilet, the most common code requires 15" either side of center for a toilet (i.e., a minimum of 30", which you could meet). Now, with a wall-hung sink, you might get by because your knees would likely fit underneath it, but standing back up again might be messy!

You need to find out what the minimum clearances are for Toronto, then that would guide you as to what would be allowable.