Keeping yourself available
A few weeks ago, I sent out a batch of yellow letters to Tulsa County probate personal representatives. I've gotten a few calls and texts, but I got one yesterday that seemed like a great prospect, motivated seller from out of state. I had a doctor's appointment to go to with my wife (we're having a baby Monday and this was her last appointment before that and we had some questions) and a pre-op for her at the hospital this morning, so I told him that I'd be able to look at the house today after we got done this morning. So I called him afterwards and he said "I meant to call you but I didn't know what time your appointment was, we just signed a contract on the house."
So the moral of the story is, before sending out a marketing campaign, make sure you can respond to any leads ASAP. If I had been able to go look at it yesterday, I'm confident I could have made an offer quickly and had a deal. Not saying you have to do real estate investing full-time or not at all, just keep yourself available and be able to go look at houses after hours or whenever you can (I wasn't, and it came back to bite me.)