In my experience, part of the job of an estate agent (especially one charging 3%!) is to vet potential buyers, and advise you accordingly. However I suspect they have an obligation to pass on all offers to you, regardless of the status of the buyer. You then have to form your own view. By the way, which part of the country is this? Our local agents (North West England) are charging from 0.5% to about 1.5%. I sold my house with an excellent one at a negotiated rate of 0.8%.