Single Phase / Three Phase supply

[flameport]

would this be enough power for what I am currently proposing

Not even close.

UKPN would need to upgrade this to a three phase fuse?

There is no use for 3 phase in dwellings, so if the shop is going to be converted into a flat or whatever then 3 phase is irrelevant.

and to get UKPN to move this to the communal hall way, get the utility provider to install individual meters and then an electrician to do their part?

If you are keeping the shop as is for now, then you need 3x new supplies installing, one for each flat and a landlords supply.
UKPN installs the cable and cutouts, you then need an energy supplier to install metering.
Electrician does the internal wiring, consumer units and whatever else.

If/when the shop is converted, it already has it's own supply for that.

 

[JohnW2]

If you are keeping the shop as is for now, then you need 3x new supplies installing, one for each flat and a landlords supply.
UKPN installs the cable and cutouts, you then need an energy supplier to install metering.

Indeed (essentially as I said). However, as I also said, if the DNO were asked to provide 3 new supplies for one property, is it not pretty likely that they would take all three phases in to a 3-phase head? ... then, as we have both said, the supplier can install one meter on each phase ??