Typically, even if you did not sign any agreements, if you asked an agent to show you  property, you will owe him or her his or her typical commission (or if his or her "typical" commission is unreasonably high, the normal or customary commission for an agent on that type of transaction. The need to pay can be derived by contract law (there was an oral, or even implicit, agreement between you when you agreed to see a home shown by the realtor) or by unjust enrichment (you are "unjustly enriched" if you found a home because of the agent's contacts, work, expertise, etc., but then refused to compensate the agent. If you don't pay and are sued, there's a good chance the agent would win; you may therefore want to try to work something mutually agreeable out in advance. Good luck.