"Like new 9500 mi." sounds great but can still be very deceiving.
You will find many members on the Monaco/HR forum tell you all the basics;
How well have the tires and batteries been cared for. What is the overall condition of the coach Inside and out. How was it used by the previous owners? Its a general consenus that everyone replaces Monroe shocks at @ 10K. How are all of the house items.......Aqua Hot system, power cord reels the Fridge and so on and so on.
As far as the telescoping slide goes I don't own one personally, look at the slide rollers, the seals and look for damage above and below ALL the slides, even the electric ones in the back.
Plain and simple use your common sense.
My wife and I have a lovely 2008 Scepter that we purchased last year with 9000 mi on it. Guess what - Its still taken me the better part of a year to get everything STRAIGHT on it. Tires, batteries, Power cord Reel, Water Hose Reel, New Aqua Hot Boiler fluid, Leaking Slide Hydraulic Pump, Windshield leak and so on. Switched to a Residential fridge. Now I have a excellent Scepter......
Bottom line is it will need some things. Its pretty safe to say that the Cummins and Allision are excellent and should not have been abused much since 2011.
Good luck and let us know how you make out!