Lenders were hesitant to loan for investment properties, especially in condo complexes with low owner occupancy rates.
In 2012 I learned that I didn't look hard enough when I a buddy told me he 'had a guy' that he'd get loans from for the same thing for 20-25% down. He said it was a bit shady and the rate was a bit higher than a conventional loan, but it did the job.
And to be honest with you, in all of my investment I've never crunched the numbers to determine exact ROI. I always ballpark it in my head and go with my gut. I'm sure it's more risky and I'm probably leaving money on the table, but to me investing was a hobby and that kept (keeps) it fun. I do it because I love doing it.
Also, it may be holding me back, but I don't like debt. The last three homes I bought cash, as well as both of our cars. Hell, I'm even self-funding my business. I find it gives me a lot more freedom albeit a lower return. But to me it's worth it. For example, sure I could grow my business faster with funding, but I've been working on it for two years now and still love it. In fact, I'd do it for free. You can't put a price on that.