1,528 customers weighed in most favorably on GE's Personal Security Window/Door alarms (2) for $8.61 this week at Amazon.com.
The copy reads that they are easy to install and require no wiring, and mounting "hardware" is included.
You can set these to a 90 decibel door chime, an ear-splitting 120 decibel alarm, or off for when you want to open up your doors and windows. They are battery operated and you will have to regularly check the low battery test button to make sure they are still charged. These attach with double-sided tape, so you'll also need to check now and then that the adhesive hasn't melted off. (Oh, the joys of living in the Mojave!)
120 decibels is louder than a rock concert at 4-6 feet from the speakers, so you will hear it. Your neighbors, if they live within a mile, will probably also hear it, so you may want to let them know you have an alarm if you're on speakin' terms.
These can also be easily removed and reused in hotels or AirBNBs for added security.