WiFi Hot Spot Question

I'm thinking of getting an R2 assuming I can get a charger installed. I live in a condo building so it might be cost prohibitive to have one installed. We have "right to charge" laws where I live so I'm not concerned with the HOA board. What I'd like to know is, how long does the wifi hotspot stay on once you've been parked for a while? Most of the chargers I've seen have a wifi component and being in a parking garage my home wifi won't reach. Can I just use the R2's hotspot or does it eventually shut off?