This is a bit tricky, because a great agent has been trained in the art of sales. We examine everything, like body language and your words are so important. Even the eye dialate when a person is lying. Maybe they touch their face a lot and I know they are hiding something.
So talk in person if you can to read that agent or sellers body language. If your over the phone chose your words wisely.
Don’t submit a dumb low-ball offer on a house you want. This can piss a seller off and he may not want to do business with you.
Have your pre-approval for the amount you offered. If he sees you have more he is enticed to ask for more.
Look for faults in property… Anything and every excuse we can to show the seller all the repairs we need to do. Get a contractor to make you a free quote. I can do this as I’m a builder as well so find an agent with construction experience.