It depends upon what the spacing is, and whether or not there are kneelers of the sort usually found only in Roman Catholic churches. You might be able to do these areas with the Oreck Orbiter XXL. Oreck sells these for $500. I can get you a new one for $300, plus about $35 for shipping.

Excellent for most types of theater or Church work. I can put my Challenger between pews with ease. Underneath middle rows with bench type seating can be a problem with any machine