Question about day to day use of Nest

[Deborah Metzger]

My husband and I just purchased our first income property in Florida. I've been reading reviews of other condos to get an idea of the do's and don'ts. 

One thing that has come up a few times is guests being frustrated they couldn't control the temperature or had to contact to owner to lower or raise the temp. One even said "thank goodness our condo didn't have the Nest system so we could actually control the air."

The unit we purchased comes with a Nest thermostat. I've tried reading up on it but can't seem to find an article telling me practical information. We definitely want our guests to be able to control the temperature. Here are my questions. 

1. Can you literally just walk up to a nest and turn the air up or down? Or do you have to download an app? Worried about older guests. 

2. I like the idea of us controlling it remotely when no guests are there. Is it easy for them to over ride it or how do they/we take control back?

3. I do like the idea of advertising that they can remotely turn on the air on the way home or turn it off before getting out of bed.  Is this something I can offer? Or does only one person with a code (me) get to do that?

We don't close on our condo for another month so I can't get in to fiddle with it. And once we close we'll need to start renting pretty quickly, so i'm trying to learn as much in advance as possible. 

Thank you for any information!!