Lead generation techniques for flips and land: cold calling / texting vs direct mail

[Sebastian E.]

I recently started investing into lead generation to generate leads for flips and land deals. I have 1 full time cold caller, 1 full time texter and a part time acquisitions manager. This is my second foray into lead generation. The first time I did I paid for the lists and had a full time cold caller and then I was doing all the follow up and acquisition work myself, which was fine but I am hoping I can generate more leads this way. It is a fairly significant investment for the size of my business but in order to grow the business I know I need to be generating more leads to be able to increase my volume. I operate in a mostly rural area in the Eastern Panhandle of West Virginia and some adjacent counties in Maryland and Virginia as well, which poses a challenge in that there is not nearly as much population density and therefore not as many potential properties. 

I am wondering if there is anything else I should be doing or other strategies that I have not thought of such as direct mail. I haven't tried anything in the way of google ads or SEO or anything like either. 

Would appreciate any thoughts you all have from your experiences generating leads particularly in more rural areas. 

Just for reference I have flipped around 20 homes, a few multi family properties and my two most recent deals were raw land.