How does someone explain the cost of 10 quarts of fluid and an hour labor totals up to $1000?I don't think it would really be that bad for the engine if the oil was only changed once a year, as long as it wasn't more than 5000 miles each time. I think an oil analysis or having someone look into the engine with a scope would give you a good idea of the shape it is in. Expensive scan tools are also good enough that they will tell a mechanic if the engine is running right and if the transmission is shifting correctly. I don't think that you could really reverse any damage without completely rebuilding the engine/trans or getting new ones. I personally would just change the engine oil and maybe get an oil analysis done since you would be changing it anyways. You could have the trans fluid changed, but from what I read it is at least a $1000 job. You could also have an independent mechanic look over it really well and see if there are any issues. If it is still under warranty, you could try to get them fixed under warranty. I am sure someone who is more mechanically inclined than me can offer more insight. If you buy a car like this in the future, I would recommend checking the Carfax before you buy it.
I think that it will be fine because it is low mileage, not much time for someone to do a lot of damage to the car.
This is also why I wouldn't buy a leased Hellcat. I don't trust people to take care of leases.