Use a google form, it dumps to a spreadsheet
https://gsuite.google.com/learning-center/products/forms/get-started/
As far as fields go, you probably need name and date, possibly address if it is neighborhood focused (4k in a neighborhood! wow!)
Use an online QR Code generator once you have the URL for the form to be filled out, print that on your fliers, etc.
Consider registering a domain name if you can come up with one that is topical, easy to remember, non ambiguous in spelling, etc to put up a splash page explaining it all. If you do that, shoot me a PM I'll host it for you.