Mark, I'm from the school that believes you shouldn't bid by the square foot, but...... $28/sf?!?! Unless that is a very elaborate design with lots of cuts, difficult excavation and poor accessibility that number seems excessively high.
If you have some paver experience, I would think with good access, you'd be able to knock that out in a day (maybe a long day) with another guy.
Green Monster Landscapes
"Blue eyed boy meets a brown eyed girl.... oh oh oh the sweetest thing"