The really simple way would to find a lock of similar [or slightly larger] dimensions to the ones already fitted, and swap them over, this will mask any timber and paint discrepancies showing where a new latch has been fitted.
OK fit one top and bottom of the sash, this will possibly mean that you are left with a mark or marks where the original latch was fitted ?
As an aside, if your Insurer needs to ask about the window sashes being locked, just tell them you have misplaced the keys and cannot locate them at present.
I do not understand why insurers are so insistent about such latches, and Bugler can simply smash a window and gain access, it appears to me like an old fashioned view on security??
Ken
