How to market to Americans when you never set foot on US soil? Is it even possible?

My name is Ahmed Magdy and I'm starting a business targeting US real estate investors and agents/brokers. I'm a telecom engineer and a certified project manager, who used to do some freelancing as a software developer on the side. One of my freelancing gigs with a veteran American real estate agent inspired me to start this project and share it with the world. Well ... the US world. My project is a little software gadget that should save a lot of time for investors looking for rental properties to buy-and-hold. You can read more about the tool on the website. Having almost no money for marketing, I created pages on social media outlets and a MailChimp account. I signed up to the BiggerPockets community forum. I reached out to my two American contacts in the real estate business to help me promote the thing. I created a Kickstarter campaign mainly to generate leads. Those are the few ideas I had. I'm still starting, so I cannot say I failed yet. But the results are certainly not what I hoped for. Anyone in here has gone through similar experience? I'd really appreciate any tips or pointers. Or is it impossible and I should cancel the whole thing off?