Quote from @Theresa Harris:
I'd start by talking to a bank about loans if you're DTI is already high-ie how much can you borrow? As Nathan said, what are the $100K homes like? Is that an average home in the city or is that a cheap home in a not so great area? The cheap homes may look great on paper, but the costs are always higher and tenants more problematic.
Selling one property to buy two can make sense when you have equity built up and room to borrow more money. I did that and while I wished I did one thing a bit differently, it worked out. What would I have done differently? The second of two homes I bought when I sold the rental, I would have bought a more expensive one as the one I got was close to the university and tended to attract students which had higher turn over (though it may also be my local market).
I'd also look up how to do a 1031 (I think that is what it's called, I'm not in the US) where you defer capital gains taxes on rentals by buying another within a set period of time.
Thanks for your input Teresa! So far, what I've learned from everyone's reply is to use leverage instead of buying with all cash, and to buy in a better neighborhood. And, yes, I have heard about the 1031 exchange and was planning to use that. Thanks!