Tax Questions Business Vehicle

Hello,

I am interested in purchasing a vehicle for my real estate business. I have a few questions.

The vehicle MUST be over 6000 GVWR right? Even if purchased under my LLC? I am looking at buying a used pickup truck and lots of the older ones are lighter. This would be used for moving materials around, with a trailer being rented when required.

The purchase price is depreciated rather than expensed, and over what period? I believe this is five years?

What percentage of gas and other vehicle related expenses are deductions? Such as insurance?

All repairs to vehicle would be expensed right? Would a new exhaust system, for example, be depreciated rather than expensed in that tax year?

Any recommendations on a used pickup that would fulfil the requirements of 

a. being around $10,000

b. being tenable in date night conditions

c. pull a trailer carrying anywhere from 1 to 5 refrigerators at a time?

Thanks!