I was comparing price via her nearest suppliers, below
https://www.hardwoodlogsltd.co.uk/bulk-logs-delivered.html
https://www.wirksworthlogs.co.uk/kiln-dried-logs.php
How are you supposed to test the moisture content?
If the "barn stored" stuff is below 18% I would be buying that from Hardwood Logs Ltd. Much better value than what your mum is getting now with half a ton bag for £70.
If Hardwood Logs are a decent bunch they will have no dramas about telling you what their barn stored stuff is roughly around moisture content wise.
Wirksworth are boasting that their ton bag is now ONLY £120.... jeees, what the hell was it before?!? Way too expensive IMO.
A standard 3.5 Transit type tipper would be absolutely bursting with 3m3 in the back I'd think. 3 builders bags is nowhere near 3m3 so just be weary of these people selling. Builders bags feel like short changed each time as they do not hold that much wood, a lot of wasted space. So seems better with tipper loads but you literally have not a clue how much you're actually getting that way. So just try ensure it's decent humans taking your money. Absolutely despise the fact there are people out there potentially being ripped off, it's horrendous.