What insurance is needed to pick up and deliver other people's cars?

Liability insurance

Talk to any insurance agent, but I would think any business liability insurance would cover you. Actually, the owner's insurance would probably cover any liability to someone you hit with his car, and if he has full coverage, his damage too. However, that company will probably try to recover its payout from you. Try this site where you can compare quotes from different companies: USAINSURANCEQUOTES.NET