Hi Debby,
That is classed as an <b>Intermediate</b>. A four wheel drive falls into the <b>Sports Utility</b> category and is the most expensive of all. In order of expense, the categories are:
Economy
Compact
Intermediate
Full Size
Premium
Luxury
Convertible
Mini-van
Sports Utility
The last four (Luxury through to Sports Utility), are all much of a muchness as far as cost is concerned. I reckon it will be in the region of $100-$140 a week to upgrade at the desk.