It seem strange to me a Realtor would even ask you to provide your clients with a range of repair-replacement estimates.
I don’t remember any Realtor ever asking, clients have of course, but I just give the names of three reputable contractors to the client for the particular issue that needs correcting if asked.
I have been in the building business most of my life and I still would not give anyone a price, there are way to many factors to get involved in when doing so.
Like the roof covering needs to be replaced, but the area has a vaulted ceiling without an attic and you cannot see the roof sheathing, so naturally you would not have any idea how much sheathing might be needed besides replacing the shingles, etc, until the shingles are removed, as one example.
So it would be a real gamble to give any repair estimates even in a ballpark range, the difference in reality could be significant.
Just my opinion anyway.