kick some tires

(idiomatic, colloquial) To shop for a vehicle or other item to purchase or invest in.

Example: 1993[1], Road & Track, volume 45, page 142:
  ... on standard equipment, options, warranties, safety equipment, fuel-economy ratings and - of course - prices, so you can go kick some tires in confidence.
2001, Brian O'Connell, Bill Griffeth, CNBC creating wealth: an investor's guide to decoding the market‎[2], ISBN 0471399086, page 181:
  Kick some tires. What is the fund's expense ratio, and how does it compare with those of its peers?