@TaxGuyBill With a full step-up, it is likely that amending will save the client more tax than what you would charge for your fees, so the client will want to amend.
Sheer conjecture. Let's say it's a $20,000 step-up. (I know, it could be $2,000 or $200,000, but we don't know.) So over a year and a half (I'm assuming she died in mid-2017) it's about $1,000 more depreciation. In a 22% tax bracket, that's a $220 difference. Maybe a small amount of state tax, also. You do amended returns for less than $100 a year? I'll send you some clients.
On the other hand, maybe the AGI is over $150K and we're just adjusting the carryover losses. Does that require amended returns, I wonder?
The real advantage here is to reset the accumulated depreciation.