There was a phone app that one guy in our group used. Gave location and costs of parking spots, paid by credit card and they sent a bar code over phone that guy at parking entrance confirmed.

All kinds of different lots. People's driveways, vacant lots, business parking lots, etc. Price varied by proximity to stadium.

Worked kinda like the house renting companies. People with a few spots lots available could list them on this site and the site took a cut.

I was skeptical, but it worked great and was within easy walking distance.

Unfortunately can't remember name of app - but you can probably find it with google - don't think it was just a local thing.