Perhaps others can say if they purchase their own cable due to the run was the work then carried out for free. I think @Fastbike1000 quoted he paid £250ish extra for 30 meter cable run.
I must add that the extra was for the cable and a small trench run of about 10 foot.
My view point is, if cost a little more than that it’s still going to be far cheaper on Mb than having it done if say you were not on Mb, as the total installation and charger would be chargeable.