It has been very rare in the seven years we've had the Motorhome to put our Pilote on EHU at home or away.
An 80w Solar panel keeps both the Leisure batteries and Starter battery topped up throughout the year, with a CBE CSB2 trickle charger between the batteries, and I haven't had the hook up cable out at all this year despite not being able to take the Motorhome out for a run.
The Banner batteries lasted over five years, despite rarely using campsites when abroad, and the newer Yuasa batteries also seem to have no problems.
I have a couple of LED Mini Digital Voltmeter Volt Meter Gauge Voltage Panels (a few quid each) to show the resting voltage of the batteries and can see how the batteries are when stood on the drive for any length of time – ie, lockdown.
The only drain on the batteries while stood is the Alarm system and the Solar panel copes easily with that.
I know everyone's Motorhome is different but, like me, I try to keep things simple and the Motorhome just keeps 'ticking' along without much input from me and I like to keep it that way if possible.