Great considerations all. I've thought about the situation where the appreciation doesn't materialize, and the area in general (being close to universities and downtown) is very stable in terms of housing prices. The rental market is crazy and there is generally a shortage, so I believe I'd be safe even without the value of the property going up in the next few years.
Essentially, the subway is a great bet, but even if it doesn't materialize (which seems unlikely at this point), I think it's still a good investment that'd yield positive cash flow. And soccerluvof4, I definitely may wait and pay more down myself, but borrowing is not really an issue from family... it's more of just finding the right property and being liquid/agile enough to pounce on it when it becomes available as the market is very tight.