Prep underground conduits for eletric and data cables to new garage

[Bruce]

We are preparing a new garage which we need to pull both electric and data cables to, at some point the ducting need to change from what is underground to the ducting the will run outside along the house to meet up with the consumer unit which is inside together with the network connection. I'm thinking that I should bury ducts, perhaps 2x 50mm O.D (intend for 10mm cable for potential PV inverter hense the size) and then teminate them into connection boxes on the house, the other end will terminate inside the new garage so they don't need to be water tight. But twin walled flexible ducts of this size doesn't seem to have glands or the glands cost £30 each which feels redicilous. The length undergrouund is only about 2m so could be done with rigid ducting if there is any that can be burried underground. My two picture below is for the whole length, our consumer unit is behind/indoor of the EV charger and the current carport is in the same location as the new garage, so I'm thinking that the interface between undergorund ducting and the wall conduit is near the ASHP isolator.

 

Does anyone have any idea on how to do this?

 

I feel like this should be done on many projects so I'm a bit suprised to not find a good interface between undeground ducting and rigid ducting/connection boxes.