Not a dumb question, but we will need more information like what actual modifications were installed?
As I'm sure you've deduced, the more likely scenario in these situations is that they flashed to the stock map and kept the Flashpro to sell. However, if it's as modified as you are implying, it would not be running well like that.
It's still possible they forgot to unlock the Flashpro from the car and it therefore still has the map for the modifications. People have chimed in here before admitting to doing that very scenario and therefore essentially turning their Flashpro into a paperweight.
The other scenario is that they had it mapped by a tuner with a Flashpro dealer unit and therefore never had a Flashpro unit themselves. This isn't the most common, but it is an option.
As I'm sure you've deduced, the more likely scenario in these situations is that they flashed to the stock map and kept the Flashpro to sell. However, if it's as modified as you are implying, it would not be running well like that.
It's still possible they forgot to unlock the Flashpro from the car and it therefore still has the map for the modifications. People have chimed in here before admitting to doing that very scenario and therefore essentially turning their Flashpro into a paperweight.
The other scenario is that they had it mapped by a tuner with a Flashpro dealer unit and therefore never had a Flashpro unit themselves. This isn't the most common, but it is an option.