2008 Sienna LE Prep to Parking van outside for extended period up to six months

Hi,

I read that I should fill up gas tank and add Sta-bil to fuel tank.

I am researching for an outdoor van cover (posted a thread and one answer) that will lasts two to three years in Hawaii rain, wind and sun.

What do I do about the car battery? It is in a stall with no electrical outlets so I can't buy a maintenance charger.

Can I disconnect the negative of the battery? Some sites say ok and others say no because of computer memory.

Any suggestions about the car battery?

Any other suggestions would be appreciated.

Thank you very much.

2008 Sienna LE Prep to Parking van outside for extended period up to six months