A:AnswerIt comes with one sensor that you can put in front of the doorway of what ever room you don't want it to go in. You can purchase more sensors for other doorways.
A:AnswerI don’t have shag carpet but my hardwood floors look amazing! I have different flooring in each room (not by choice) and Roomba does a great job making the transition.
A:AnswerUnfortunately, the roomba does not pick up anything, especially pet hair, up from our carpet and we have not the thickest but not thin either. I don't think it's worth its cost for little performance.
A:AnswerNo, only requirement is to set it up with wifi using the iRobot app. Once setup you need nothing to run the robot, you can even delete the app from your smart device. Simply press the clean button on the robot, the spot button once placing the robot in the spot you want cleaned, or the home button if you want it to go back to its base once it has started cleaning.
A:AnswerDepends on the size of your house. I have a 1040 square foot apartment with 1 cat. The first few times I ran it took about 2 hours and had to empty every time it came back to base to recharge (it runs about an hour per charge). Every time since the cleaning time has shortened (down to 45 minutes now) and I only have to empty every few days (cleans every day). I think if you let it run every day, you shouldn't have issues. Again, tho, this depends on the size of your house.