I fixed a parasitic drain on my car in 408 days
I have a drain on my VW Caddy Maxi but had it booked in already for a leisure battery and solar install. When the solar finishes charging the leisure battery the starter battery is then charged. And so hey presto I now have an anti-drain system and haven’t had a problem since. So if you have a parasitic drain and can’t find fix it convert your car into a camper :)