Stormin Mormon wrote:
I've also seen some odd brands of locks, that are fairly
good and commercial design. And some of them can be equipped
for Best or Arrow cores.

What the OP is describing, Titan or Kwikset Ultramax would
be a start. Good quality locks, and the core removal
capability. And master keyable.


Any idea what an interchangable core lock is worth? I would think they
would be pricey. But a nice fast simple changes.

Having spare identical locks and swapping out the keyed part (like knob
assembly for key-in-knob), as someone suggested, is pretty fast. Then,
as suggested, having the old one rekeyed.
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One source of unused keys is a locksmith. They get them when they key
multiple locks to a common key.

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Manufacturers have standard cut depths on keys (but not necessarily the
same as other manufacturers). One way to avoid the 'copy of a copy of a
copy' problem is for a locksmith to determine what standard depths the
key is cut to and use a key cutter that cuts standard codes.

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bud--