Maintenance costs? What are the big dollar items? I mean unless you're talking repairs which to me isnt maintenance really.
Lots of folks who are "on the fence" in terms of being able to afford a Hellcat sometimes don't understand what something like a brake job costs. I can't tell you how many Hellcats I've seen that get sold because the owner is someone who's used to having Mustangs or Camaros where most of them can get a full brake job done for about a grand. 3-4 grand for the Hellcat is an eye opener. Then, you have the tires. Sure, tires are tires and on most cars at this level, they use similar rubber. But, most cars at this level don't have 650 lb. ft. of torque, which means those tires don't generally last very long. So, if someone is used to buying 2 tires for the rear, then 2 tires for the front 6 mos - 1 year later, then they're going to be doing it twice as often.
Then, many of these folks buy used high-mile Hellcats, which come with an increased chance of blower failure and other powertrain related issues, especially if the car was modifed. Many of the "affordable" Hellcats were not only modified, but heavily. Thus, someone who can barely afford a Hellcat does so by getting one of these hand grenades and then the fun begins in terms of repairs.
The long story short is that a lot of people on the cusp of affording a Hellcat have never owned a car at this tier before. As I said, they're mostly coming from Mustangs, Camaros, imports. The maintenance and repair costs on a Hellcat can get ludicrously expensive. Hence why someone who can barely afford a Hellcat might not really be able to afford it if they buy one that has some special needs. If they can't afford a new one or at least a good used one that was well kept, then they probably should think twice about buying a cheap one.