Though this is my first time on freelancer.com, I am not new to writing these types of scripts. I have worked for two very large companies where I have put my PowerShell skills to work. I write PowerShell automation scripts and tools to assist our teams in doing their day to day tasks by taking complex steps and integrating them into simple functions or scripts which allows those that don't need to or want to learn PowerShell.
As for your project, I would take this approach based on the description above:
1. The script would read the necessary file locations from either a flat file or csv so that the code doesn't need to be changed to add or change a file location. This would also make the script more portable if it needed to run on different servers or environments.
2. In each location, I would have it find the most recent files or simply search for files with the current date in the filename (depending on the date format)
3. If it finds a file and presuming the file is in a format that can be imported by PowerShell, read enough of the contents to determine if the file is empty.
4. As for the email, as long as there is an available smtp relay server, I would draft an either an html formatted email or attach a csv file with the output columns per the requirements.