I fly a N/A SR22 and have a similar mission profile to yours.
Advantages with the turbo are:
Quicker climb, higher altitude limit (25,000 ft vs 17,500). Note: both types will go a bit higher, these are POH limits.
Disadvantages are: more expensive to buy, more complicated and slightly more frequent maintenance. You would also probably need cylinder work earlier with the turbo.
Personally, I fly fairly high when I'm alone (FL160 or 170) and use a portable O2 system with the Mountain High demand system. When I have passengers I stay below O2 altitudes.
Selling either type shouldn't be excessively difficult although there is obviously a specific market.
I recommend strongly that you visit the COPA website, search for this topic and then ask any further questions you have there: you will find a huge amount of well informed guidance on all aspects of owning and operating these aircraft there. You will need to register, but don't have to join. That said, if you are serious about flying a Cirrus, it's definitely worth joining.
If you would like to discuss this, please drop me a PM.