Standard QuickBooks Pro or Premier trials last 30 days. However, the version was bundled with a distinct license key that unlocked a 140-day use window . This was not a bug or a "crack"—it was an intentional marketing strategy by Intuit for several reasons:
If you need the 2018 trial specifically to open an old file or for a specific educational requirement, here are the official ways to locate it: Standard QuickBooks Pro or Premier trials last 30 days
Even with 140 days, the trial was not a "full perpetual license." You faced these restrictions: Standard QuickBooks Pro or Premier trials last 30 days