I regularly leave cars for extended periods without issue.

Alway use Esso super synergy plus (zero ethenol in most of the country)

Well the most recent issue I’ve had was with my woman’s DBS which after 2 years started BUT with a misfire/running rough.

Luckily it didn’t have much fuel in so I put 25 litres of fresh fuel in and after a few minutes it was Kool and the Gang.

Even an old Capri 2.8 was pretty good with this method after 4 years.

2000 Plus 8 4.6
2002 Aero 8 S1