What I'm after is running half a dozen cordless phones which connect to
a local (asterisk) PBX via Ethernet/SIP.

I'm not intersted in the current crop of WiFi SIP phones, so So I'm
wondering just how many DECT basestations I can run in the same location
(it's a bit warehouse, but the actual basestations might well be within
a few meters of each other) Or is there a better way? Eg. one BIG base
station with separate phones, each on their own SIP accounts?

I've found the Siemens C460IP which is a starter, and half a dozen of
those would work nicely, but I've never been able to satisfactorily work
out just how many DECT basestations I can have in the same location...

Does anyone know, or can they point me in the direction of some documents
that might explain it all?

Thanks,

Gordon