I recently upgraded to a Prevost from an MCI. I did a complete inspection on the bus and all associates components. I identified everything that required service, maintenance, and repairs and jotted them down. I assigned a retail price for the work to be completed, then determined what I could do it for etc. My offer was based on the retail repairs, and the seller was very understanding regarding my offer as I explained the repairs required. With that being said if this is a first time bus purchase, take someone with you that you really trust to help with that inspection. Surprises can come with huge price tags, and lead to a disappointing experience.