how far are the off-site parking lots that charge a lot less than the on-site lots? walking distance?

Fairly close. I was there a couple weeks ago and parked at a church for $20. The walk was about 10 minutes.

I would try the free on site parking first. We had no problem at 1:00 in the afternoon and it was a 1 minute walk to the entrance.

I would say to park closer and pay more because when you pay you less you love yourself less

Recently attended the Rose Bowl for a antique flea market event and we parked for free approximately 200 yards from the entrance gate

I would say a good 30 minutes walk