Need an agent to sell to investor?

[Bill Ward]

I have one rental property and I've never sold a home before. I occasionally receive the random texts/calls saying hey we see your property at xx we would love to buy it. Usually they're looking to buy at half value, so I assume they are investors or wholesalers. I'll respond back that I'll accept 180k as is, which is about market value, and a number I would sell for. If someone decides to buy it from me for that and move forward, do I need to get my own agent, or do I just use whatever agent they are using since we have an agreed price? 

Thanks,

Bill