any way to keep car running with remote start after I open the door?

2012 Prius Five. Dealer installed remote start using the stock key fob. This is the one where you push the twice button twice then press it and hold it for three seconds. The emergency lights flash while in remote start but the car shuts down when a door is opened.

A few problems I'm having is that first off the range stinks. I'm used to a chrysler remote start that I could turn on from the far end of my house and I'd hear the car beep twice to know it was turning on. Plus you can hear the V8 start. The Prius makes no noise so my only confirmation is to look out the window and make sure the flashers are flashing. Anyway to have the horn beep to confirm? speaking of which, does this car have a horn?

another issue is that when I'm in a parking lot heading to my car and I remote start it, it is only on for about 5 seconds when I actually reach the car. Once I open a door, it turns off. This is not what I'd like to have. If I go to costco or the grocery store and I'm loading up groceries, I would like to have the car stay on and continue to cool it down so that when I get in, it is cooler inside. Any ideas?

Thank you in advance.