Does the security system alarm call your tenant's phone or yours?

[Anna Watkins]

I'm revising my lease for signing with the first tenant in house #2, so this is a small-timer's question.  

Does the security system alarm call your tenant's phone or yours?

I've had a basic security system installed, and the first 12-months monitoring is included in rent (this drops on renewal or for the next person -- a built-in $25/month rent increase for me :-).  For house #1, I've always had the tenants put their phone on the contract, but am wondering if I shouldn't also know what's going on with the system, especially since I'm paying at first.  If so, I would have the call # be some sort of forwarding number that will relay the call to both me and the tenant.

Are there any related liability issues in being included on the alert list?

Do you have a service to recommend (not connected to a particular cell provider) that will forward an incoming call to multiple numbers?  I already have one Google voice forwarding to my cell phone, and can't set up another.

Thanks!