There are two costs--the cost to own, and the cost to operate.
Your ownership cost difference will be mostly the acquisition price, unless you have to pay state property tax based on the value of the aircraft. [Here, it is $15 per seat, so no difference.] Insurance will vary, too, and the annual will increase with more systems to inspect/repair. GPS & weather cost do not vary between aircraft unless you have multiple units, each requiring its own subscription. Either plane will obviously fit into the same hangar. Some people like to divide these costs by the hours flown to arrive at an "hourly cost" that fluctuates tremendously from year to year. [i've logged from 84 to 127 hours per year since I bought mine four years ago--no, I don't include these costs in my operating expense nor compute the hourly cost of them. I try to not add them up, not even just in my head.]
Operating expenses are fuel, oil, tires and engine reserve. You can search this board and find many discussions [some with actual costs] for overhauling/replacing engines. Allow some extra for maintenance as things are used, plus the biennial pitot-static check. My last check ended up replacing the static tubing, the ASI & Alt [it was close up to 10K, then diverged wildly above that]. This will be more critical in a turbo, and you will require an Altimeter rated to higher than the 20,000 msl unit that I have, which will certainly cost more to purchase/overhaul/repair.
Turbos also require an oxygen system, O2 refills, and every few years a new tank. Oxygen tubes, cannulas and masks have short life spans [12-24 months]; check on things like flowmeters and regulators. What about the microphone in the mask? I don't ever go that high, so I'm just guessing. High-altitude flight is a whole different subject, talk to the turbo drivers about the different addons that you will need to buy, maintain and replace. A back-up O2 system is also wise to have, so more disposable costs for it, too. But you will get to outclimb much of the weather. Don't forget things like TKS fluid, alcohol, fuel additives, etc.