If you're considering seats on the infield at the Coliseum, keep in mind that there is a reason that sections 116-118 are among the most expensive. Because the seating flares out so quickly, these are the only seats that make you feel like you're on top of the action.
The first five rows of sections 115-119 are considered Diamond Level. Not only are these seats the closest seats to the field, they come with in-seat food and beverage service and all-inclusive food.
Sections 119-122 are above the A's dugout, while 112-115 are above the visitor's dugout. Row 5 is the first row behind each dugout.