You have 3 main choices for seating.
1) Real Theater seats which are anywhere from $100 used to $400 new (and all points in between). These seats are 22-24 inches wide and may have a rocking mechanism and or cup holders. This type of seat allows for easy base shaker installation and give a true theater feel in a small space. Also, since these seats are designed for commercial use, they should last a long time in the home.
2) Berkline/Showtime type theater recliners.
I have seen this type of chair for as little as $750 for 3 in leather. They recline and may have cup holders. these seats are wider and theoretically more comfortable but in you 10' wide space you will likely only be able to have rows of 3.
3) Couches love seats and other assorted furniture.
You may already have the needed items in your house so this option may be free.
Hope this helps as a general outline.
I had a 20amp circuit run to my closet for equipment. In this type of a setup, you maximize the space in your theater and don't have to worry about getting an expensive rack.