are you looking for multi tenant park slots ?

i need the simplest, most efficient way to do call parking in the multi tenant model

I assume in /etc/asterisk/extensions.include
you need to add include => parkedcalls under your restricted, internal-redir, emergency sections

in sip.conf
you need to add for all extensions (or you can add it through Thirdlane)
parkinglot=general

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if you want to create one parking lot per tenant (and this is the way I'm doing it)
in features.conf
you create after general section
[parkinglot_xxxx] ; section must start with parkinglot_
context => parkedcalls-xxxx
parkpos => 8001-8010 if you need to have different parkpos

[parkinglot_yyyy]
context => parkedcalls-yyyy
parkpos => 5001-5010 if you need to have different parkpos
I was not able to set a slot different than the general one, so all my tenants have the same pilot

then in extensions.include
for tenant xxx in restricted, emergency, ... section
you add include => parkedcalls-xxxx

for tenant yyyy, you add include => parkedcalls-yyyy

finally, in sip.conf
don't forget to add for every extensions you want to allow park calls
parkinglot=parkinglot_xxxx or yyyy

nice work finding out what version of asterisk he's using first .. the solution is very specific to the version of asterisk.