Get one of the lidl or Aldi smart chargers and top it up every 2 weeks
that. Fit the hardwire kit if it comes with one(I know Ctek equivalents do), and all you'll need do is open the bonnet and plug/unplug the charger as necessary.
All of the manufacturers of toys(Ferrari, Porsche, Aston etc) supply these type of chargers, with their own branding, for cars that aren't used very much.
I second the advice for a ctek charger mxs 5.0. Not cheap at circa £70 but has a few advantages over cheap versions from aldi and Lidl (I’ve had both):
1) You can buy a quick-connect/release plug that is permanently attached to your car battery. Not only does this speed things up, it also allows you to close the bonnet and lock the doors of your car. The extra lead is called a ‘comfort connector’ and is only about £7 on Amazon. I also recommend the 2m extension lead for circa £12.
2) every aldi and lidl charger I have used have produced sparks when connecting them to the car battery. I’ve never had that from the ctek chargers I’ve used.
Top Tip: if you are very forgetful like me, and are concerned about driving off with the battery charger connected, get into the habit of leaving a note or the empty battery charger box on your drivers seat: this will remind you to remove the charger before setting off!