My buddy has a Viper 2way alarm & parks underground. He's on the 6th floor and his works fine. Pretty sure its Viper...

 

I have a compustar cm4000, live in an apartment with underground parking. Although my parkade only has 1 level, and I'm on the bottom floor, I'm still on the other side of the building VS my car. I can still lock/unlock and remote start my car.

 

Thieves are getting bolder though, sometimes nothing short of camping beside your vehicle with a shotgun would stop them. Friends of the family just had their (2008, I believe) Honda CRV stolen from work, in broad daylight in an outdoor parking lot. Apparently they broke a window, couldn't start it due to the anti theft device, and the coffee truck guy witnessed them pushing it out to the road and towing it away. So don't rely on parking outdoors to stop a determined thief.

 

I know someone who had a BMW with a crazy alarm system and actuators which made the seat go all the way up and fold down so there would be no way someone could drive off with his car. Also put a few ear piercers under the dash and stuff. He was pissed when he came out and the car was gone, bustards just picked it up with a tow truck and gone.

 

^^^^ should of put a 160db train air horn behind the front bumper!

 

Compustar 900fm SHOULD be able to do the job.... maybe have someone with theirs try it out??

if i still had mine, id offer (if i was in the area)

 

I just tested mine. I went up to the top floor (4th) from one side of the building to the other and had 100% signal. My car, as said above is 1 floor underground. I'm surprised it worked since my building is 90% concrete.

 

I use mine from the 18th floor of my condo all the time and my car works in the basement, mind you its only a 1level underground parkng but it does work from the 18th floor and i just have a compustar alarm with a 3000ft range i believe. I duno about a 2story underground though thats a bit difficult to say. I should also point out my balcony faces north and my car is underground on the north side of the building. I know my brother-in-law's compustar with a 6000ft range works even from by my elevator when his car is in the basement, but hey thats just my experience with these alarms mayeb someone else will have something a bit more specific for a 2story underground