@Matt Turcutto You've received some great suggestions, and I want to offer my input because you're not too far way from achieving success. Your persistence has gotten you this far, and I'd hate to see you quit after you've come this far. I did read a few things in your initial post that should be tweaked immediately. Firstly, I think your main issue are your lists. You're not focused on the right zip codes and prospect group, which is why your message isn't being well-received. I always qualify my target zip codes and check how many cash sales there were in the previous six months. If there are 100 cash sales in one zip code and only four in another, I'm going to go with the zip code that has 100. The reason being is because there is a lot of investor activity in the zip code with 100 cash sales. The prospects are already getting mailed to by investors so they know the benefits of working with you, and these will likely be blue collar areas with a lot of homes with equity. It may take some time to qualify the zip codes at first, but you'll thank yourself later. You want to use List Source to pull all of the cash sales in your target area and choose the zip codes with the most cash sales to market to.
Secondly, I don't think your number of leads per list is large enough. While you may be targeting over 1,000 individuals per month, you're not focused enough. Rather than doing four separate lists, I would focus on one or two and hit those consistently. The smallest campaign I ever ran was a list of 390 names and that was a very specific neighborhood that had a lot of dilapidated homes. I typically aim for at least 1,000 prospects per campaign. I would suggest discontinuing the first and fourth lists, unless there have been a crazy number of cash sales. Also, if you haven't filtered by equity then your list is essentially worthless as a cash buyer. Not having equity filters on your lists is like shooting in the dark. These homes could be upside down or only have 10-20% equity, and you won't know until the prospect calls you.
Lastly, I want to touch on your marketing piece. You should really do yellow letters, or at least have your typed letter in an invitation envelope with "handwritten" font to increase your open rate. While you may not immediately close on these deals, it will at least initiate the conversation and you can followup with the leads. Every one of my deals, except for one, came from consistent followup.
I think your biggest issue is the lists you are targeting. If they're not solid from the start, your whole campaign will fail. Direct mail can work; however, it requires research and not deviating from what's worked for other investors. I spent about five solid months intensely studying the BP forums back in 2015 before I sent out my first letters, and I'm glad I waited. I was on a very tight budget, and we really only had one shot to get it right. Thankfully, we were able to pull a deal from that campaign, and we haven't looked back since. I know you're discouraged, but if you want to invest in real estate for the long haul, then this will be the first time of many that you spend money and not see an immediate ROI. I was definitely breaking even in my first year because I was learning and spending money experimenting with what works.