Yes, it's best to use one agent at a time when you're buying a home. If you feel compelled to use more than one realtor, your current realtor may not be the right fit for your needs. Every real estate firm has a contract with a list of rules. If you are looking for a firm with more flexibility, you should try searching on UpNest.com. The platform has a wide variety of agents with different requirements. You may find an agent that meets your standards so you don't have to approach or use multiple realtors at time.