Replaced ECU Hours? '08 RLXi, Hammerhead

[ftlbs]

I'm looking at a 2008 Response LXi with the Hammerhead 383. This boat has been upgraded to Zero Off and I have a concern/question. The current owner has owned it since 2014. When he bought it, the hour meter showed only 50 hours, but it had been upgraded to Zero Off by the previous owner. For this reason I'm assuming the ECU was replaced in order to add Zero Off and as a result, the hour meter was reset. He is now selling the boat and the hour meter is showing 125 hours. He is telling me that he "estimates" that the boat probably has around 400 hours total, but has no information or proof to support that. Is there any way to know or estimate how many hours were on this boat before Zero Off was added? Any tips or things I should look for? Or should I just avoid this boat altogether?

[COOP]

No way to know if the ECM was changed. Thats where the motor hours are stored.

50 hours when it was already 6yrs old, seems low, not impossible, but low. 

Ive never had to replace an ECM to add Zero Off or Perfect Pass.

[UWSkier]

2008 would need the E-controls ECM.  Lots of times people will write the original hours somewhere with a paint marker when they swap out something that resets the hours.  Have a good look in the engine compartment.