I just purchased a 2014 with around 30,000 miles. It was my first RV so I didn't have a lot of experience or know really what to look for.
I have not seen any reports of common issues with the Seneca so I just did my standard 'used vehicle inspection'. If you already have a 5er then you are probably familiar with all of this...
Before I went to go look at it I just made a mental note of the things I would be willing to fix on my own dime. I figured that I got a good enough deal that I could afford $X,XXX dollars of repairs and still be happy. This eliminated small things like broken trim pieces, cabinet doors, toilet, sink, and even some bigger things like if 1 air conditioner unit didn't work or even the hot water heater. This saved me from having to spends hours examining each little component and gave me more time for the big stuff.
That plan left me with just a few major pieces that I could not afford to repair/replace for my $X,XXX. Things like:
- frame damage (I checked under the motorhome carefully for any signs of damage)
- slide problems (made sure they went in and out like I thought they should),
- generator (those things are almost $10,000 new so I spent some time and made sure it was in good shape)
- floors (made sure they were solid and not rotted from leaks)
- Leaks (looked for any signs of leaks)
- Roof damage
- A/C units work correctly
- Engine & drivetrain should be under warranty so I was not worried about those but I did inspect things that would not be covered by warranty like mouse damage to harnesses or air filters.
- I also looked for any signs of DIY 'handywork'. I didn't want a bunch of spliced wires and cables ran all over the place. There was a crappy brake controller added to mine but that fell within the limits that I could fix myself. I made sure all of the wiring looked factory and that no shoddy looking work had been done to the motorhome.
My theory has always been that if it LOOKS like it was cared for properly, it probably was. If it LOOKS like it has been beat to death, then it probably was. General condition will tell you a lot (though not always the whole story)
Anyway. This is the method I used and it worked pretty good for me. Your mileage may vary. Hope that helps.
2014 Seneca 37FS