Swingman wrote:
....

Unfortunately, as I builder, I rarely see a window company around here
include redoing sills in the price of new windows unless it is specified in
the contract at extra cost. ...

While I suggested OP tell the window company rep to "fix it", I'm sure
their contract is written to allow them to claim it's not in the scope
of work.

That said, I think it sucks weenies as a practice as one can be sure the
sales rep didn't point out the likely or possible problem or that it
wouldn't be covered when making the sale and it certainly is a detail I
think virtually any homeowner would expect to be "made right" as part of
an installation simply as being part of the "workmanlike manner" clause.
Leaving a noticeable gap when done just isn't up to snuff imo.

$0.02, ymmv, etc., ...

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