Google Maps Database

A client of mine is wanting to add in a page with a google map that shows garage sales for the county (it’s a county news site). He would like to start from scratch (not use anybody else’s content or data) so I thought about having a form above the map that links to a new table in the database with just an address and two dates (date of event and expiration date(3 days later)) that google maps could get the info from, however I would like even better to do this via a flat file as I can’t run cron jobs on my server to delete the expired entries (and don’t want to have to manually delete them all the time). I figured with a flat file I could actually keep a running tally and every 6 months year skim the expired data out but keep it for reference. Simple enough? Any suggestions? Anybody want to help?