driveaway awning

Having just got a romahome 40 I am keen to get a driveaway awning for it but it seems to be a bit of a minefield as the van has rear entry /exit and the door is quite high ,this causes it to foul the tunnel on most of the driveaway types we have seen .We could get a side mounting one but it would be so much nicer  to be able to have the space added to the rear for ease of access etc. anyone managed to overcome this problem I would be grateful for advice before we make another expensive mistake.