What would it actually cost to migrate your system? Three factors drive most of the answer.

Not a pitch. Just the honest variables.

Migration estimates vary wildly - because the inputs vary wildly.

Three factors explain most of the variance:

1. Data complexity - not volume. How clean is it? How documented? How many special cases?

2. Business logic depth - how much of your actual process is encoded in the system vs. in people's heads?

3. Integration count - how many other systems need to talk to the new one from day one?

Get honest answers to those three questions and you're ahead of most migration conversations.

The full picture is always more nuanced. But these are the right starting questions.