My place is in downtown SF, when I charged lower, I got party kids finding beer bottles in trash along with condom wrappers but once I raised the price along with great ratings, I got working professionals and conventioneers which are never home because they were here to work.

The serve Tap/can/bottle beer and they have food to order...I like sushi bar when I’m in a hurry.  

Walmart in China sells $1,000 bottles of wine my friend.  

Being single makes this easy...suitable payments for crashing on a friends couch are cases of beer/bottles of booze/tacos/etc...or even some cash for rent if you are there long enough. 

I leave cheap granola bars on the table and a bottle of water in the fridge for each person staying. 

Then follow it up with a fantastic thank you note and a nice bottle of wine or whiskey. 

When I first started doing lending in Detroit.. this was an issue ... my client a big time flipper rehabber always had retired cops there with a clip board to check in the workers.. it was determined early on that much of the theft came from the exact guys that put the stuff in during the day.. they had the codes they knew what was there they would come in at night and steal it .the day cop and clip board put that to bed.So I agree with @Bryan Bannach  hire a retired policemen have him there during construction hours its the cost of owing property in the hood.. nothing unique about this.or just sell the property and buy something else.. but I think your looking to assemble so I know you probably don't want to sell.so just as stated hire security and I really like the idea of the @Patrick Liska  Cinder block fence I would for sure do that.. then put broken bottles in the concrete on top..

It's not like a car radiator, where some of the coolant can evaporate out over time.The Trane system I had installed at my residence was really slick - the installer put a specified amount of Freon in it by hand, plugged an electric valve on his Freon bottle into the outside A/C unit, and pushed a "fill yourself up" button on the outside A/C unit. 

My advice is to get a nice big bottle of 41% glyphosate concentrate and a pump sprayer and get busy on your backyard.

Someone left me a nice (and huge and stinky) “present” 💩in the toilet that had a seat, but no running water 🤦🏼‍♂️Turns out large bottles of draino can work wonders...Anyway that flip had a lot of headache stories.