Closing the top floor vents in winter allows heat to rise, so the top floor isn't so hot while the lower floors are cold, or open the top vents in summer to allow the cold air to flow downstairs.And don't correct them when they use the "real feel", or "feels like" temperatures they have been reporting, just to make people feel as if temperatures are hotter than they have ever been.

Next to his room is the office which has 2 windows this size but gets the hottest out of any other room, it gets so bad that I have to leave that room shut, so the heat doesn't come out and make it even hotter.

When the market was a little hotter in the recent past, a lot of listing agents in my area would shun or downplay offers that came with financing from credit unions or "too big to fail" banks. 

Depending on where you're investing, is there areas that are hotter than others?    

I didnt have many bookings created a month from arrival.

How did you arrive at a 50% CoC?

If you were and lose the value of the rental, then subtract the rental amount from the total price to arrive at the reduced value to you.Are you asking HOW to negotiate a lower price based on this uncovered information concerning the property condition?  

Additionally, provide guests with the app and access code programmatically before their arrival date so that they can access the property.

As someone with tons of hot tub vs outdoor bath experience in hotter markets (Houston here), I think adding some type of amenity like this crucial.

People have keyword alerts set up, and then someone arrives and pitches their town, which then triggers a lot of other keyword alerts to be triggered.