What would you expect instead?
I never suggested that I'd expect anything different.
A charge every month might stop a battery from expiring completely, unless its very old. However, its a far from ideal duty cycle for any lead acid battery and you can now have a reasonable expectation that the likely remaining life of each to now be at the lower end of the likely range.
That said, a dealer could have dozens, even hundreds, of vehicles on the pitch at any one time and it's clearly impossible to keep them all on a continuous smart-maintenance charge. Nevertheless, its another red cross, albeit a minor one, against this as a vehicle to consider purchasing. When youre asking why the services werent done, and whether the brake fluid was replaced at 3 years, and whether the dealer will pay for repairs in the event the warranty won't cough up for a fix because of the missing history, you could see if they'll chisel off a few hundred to cover the cost of new batteries.
To go back to your OP, if you're still considering buying it after all these slightly smelly discoveries you really would be well served jn and AA or RAC check (theyre both usually incredibly thorough) and a professional habitation check. None of these issues are major but as a whole they dont paint a picture of a vehicle thets been slathered with love either when in use or while on sale/storage, which isnt an auspicious start to proceedings.
You asked the question with your OP, there it is my friend.
