Can you please advise me if the Blue Tits and Great Tits would use bird houses (or nest boxes if that is the better term) if two were to be mounted inside of my balcony on the west, brick wall at the open south end about two metres high.

The three numbers are feeding stations.
This would be just above the roof of my bamboo pergola structure. It is also well hidden by raspberry leaves back there and the birds' beloved cherry laurel bushes are right around the corner.
I do fear both a severe winter this year plus a radical trimming job (against the wishes of my neighbor) by our incompetent garden crew.
I would be very thankful for your input on the matter.