Founder and Owner of ModernBlox, Enable Robotics, Aerovision Productions, and the International Mercury Robotics Organization. Electrical engineer at ConocoPhillips. Start-up advisor.
I am doing something very similar right now with shipping containers. Personally, I don't think you should try to raise start-up funding for a business like this. If your credit is great, a small bank loan is all you need. People do this all the time and you're at an advantage because tiny homes are so cheap! If you don't want to take a loan, start looking locally and network with a developer in your area. They may have the Capitol and could be interested in a project like this (that's what we did).
I am only responding to this question because I have recently done the exact thing. It may not be the best solution for your question but in my case this was something I started doing with 3 other friends. We all have other sources of income but really like building and designing things so we have recently put our money together and started repurposing small shipping containers as homes. Start talking to some friends or colleagues and get a feel for who might be interested in doing some projects on the side to bring in some side-income. Are you hoping to become a developer or just a property owner/manager?
For starters I think this is an awesome business model. I have been using a virtual assistant out of the Philippines through UpWork for the last 9 months. My first suggestion would be to try it for yourself.. Get a feel for the business model and maybe see what can be tweaked or modified to provide a better experience for the customer. After doing that THEN you should consider a good marketing strategy before entering. I looked at 12 different services for virtual assistants before I settled on UpWork, so whatever you build is going to need some good exposure and SEO!
I hate to say this.. But both! When getting the ball rolling on a start-up, you want to attack all possible marketing outlets. Now, if budget is the bottleneck then I would consider running some analysis on your target audience and see if your users for your service will most likely be using Google to find you (SEO) or will they be more commonly found on Facebook (Facebook ads). You can open a Facebook page for your business and watch it's activity and traffic (analytics).. Take that analysis and then compare it to what your website sees through Google Analytics. This should tell you early on how people are finding your services, in return you will know where to put your money.