Create API that can load Real Estate Properties on a third party website.

I am looking for someone that can create an API scrip that can allow our Real Estate properties listed on our main website to be automatically showcased on other third-party websites that want to load the API plugin. The API will simply load a carousel of properties (same as shown on the bottom of the main website [login to view URL]). I would like the user to be able to configure what states to run through the carousel. The configuration will be done under the Users Profile account. I have included a screenshot of the carousel for your review with comments. When someone clicks on this "More Info" button I would like it to act as a Lead Capture tool for the client. This means a simple form will come up asking for "Name, Email, and Phone Number" in order to be redirected to the actual listing; and then email the information to the client. Once that is done the client will receive the email with the content entered and basic information of the property that was clicked on including the URL to the actual listing. The customer will be redirected to the actual listing on [login to view URL] and the Property lister will also get a copy of the Lead along with information of where the lead came from via an email. Thanks