M.I.T. Maintenance and Income Tool is a freeware tool of Tom Aguilo and Robbie McElrath that reminds me FS Maintenance of Lago (FS2002 !). After the manual install in the FSX aircraft folder you are interested in, you virtually purchase your airplane, and start flying.
Upon your logged hours and way of flight, you will have to proceed repairs and checks to maintain your aircraft. C checks will be very expensive but you will get it back to a brand new status. More info in FSdeveloper forum, or directly for manual access with download link here.