I had a similar issue with my install, Glos Guy, my main meter/consumer unit is some 30m from the back of the house where the charger was to be fitted. 1 floor lower than the rear of the building and 2 x 1m stone walls (and a few lathe and plaster walls) to navigate.
We were also on a looped supply, so I had the DNO unloop us and fit a 100a incoming fuse,
I used a secondary consumer unit we have on the top floor to feed the charger, it needed changed anyway as it was the old glass fuse type, so a new larger metal one was installed giving plenty of space for the new RCB the charger needed. The cable was then run from the rear of the consumer unit up into the attic then over all of the rooms, through the stone wall where the rest of the electrical cables were run and then down into the rear basement, back up to the wall where the charger was to go. A 25m cable run. No visible cables, no trunking. We couldn’t get any of the large national installers to do this, they just ignored our applications, so we used our local electrician, cost inc. the consumables of 50m of cable, 2 RCBs (the EV one is about £30) and the outside double socket was £250. The consumer unit changeover was £200 odds, but it needed done anyway as the old unit was approaching 60+ years old & several of the fuse holders were crumbling/cracked. We did that about 6 months before the EV install, and changed the main consumer unit at the same time.
I asked the electrician about running the charger off the consumer unit with regard to wiring and he was adamant that it was not an issue, the cable thickness from the main unit to that one was more than capable of handing the extra 32a.
The charger I selected offered all of the latest protection/PEN fault, so nothing else was required. I had the electrician run another cable beside it and fitted an outside socket, so I could upgrade to two chargers later if I needed it without running cables again. The charger is from Viridian and is not smart – so it was only £300 delivered. Their advice and service was excellent.
I tried using Motability’s free service, at the time it was BP Chargemaster – truly awful and never heard from them after their initial confirmation. Same from SSE, our electricity supplier at the time. Podpoint also ignored us, so I gave up on the big installers and called Viridian, ordered the charger and sorted the rest myself.
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