Seven years is deemed the reasonable amount of time it can take to establish a good credit history.
Minimum is average age of 2-3 years.
The older the better but in some cases that isn't possible without tradelines and their are many factors at how good the results will be.
Ex. Clients average account age was 2 years 11 months. Only secured $41,000 in funding after adding more personal depth to profile. Profile had a lot of builder accounts. Credit age is factored at 15% of the total FICO scoring model.
