Stocks themselves won't do it but stocks+options can get you there. But the big question is whether to focus on paying off student loans first or begin investing in Wall Street now or start with buying a home (since renting is essentially throwing money away)?
Stocks + options could theoretically get you there. It could also get you a number in the negative arena. Even highly seasoned investors with finance degrees, CFAs, CFPs, who work on Wall Street, etc. avoid options, especially speculative options trading. If you want to do some covered calls have fun, but assuming you will get 20% long term in stocks + options is highly unrealistic. Even the hedge fund managers who get paid millions/billions to pull off what you are talking about fail the vast majority of the time. To use medical analogies: if investing in index funds was taking someones temperature getting 20% returns annually with options would be experimental brain surgery to remove tumors from around the [insert part of brain I don't even know about]. It's borderline impossible and shouldn't even be attempted without decades of schooling and experience. Start with a simple portfolio of index funds, learn a whole lot more, maybe try some covered calls, and then look at options trading.... (and if you still think you can average 20% returns... keep learning till you decide you can't.)
"what is a more reasonable goal for stocks? SPY yield itself was 13-14% in 2014."
And it was up over 30% in 2013. Doesn't mean anything. Looking back LONG term that is not the case. The Vanguard 500 index(tracks S&P 500) has averaged about 11% returns going back to 76, and only roughly 7.5% returns going back 10 years. Given current valuations going forward I would keep a 'safe assumption' of 6% annually, hope for 8%, and pray for 10%. If it averages more than 10% we all get to throw super even earlier retirement parties!!!
Vanguard 500 index:
https://personal.vanguard.com/us/funds/snapshot?FundId=0040&FundIntExt=INT#tab=1a"What's the "yield" of a real estate (I am thinking 1-2 bedroom condos in northeast, in substitution for renting)?"
The value of the building itself goes up with the cost of inflation for building a new one(labor+supplies). The 'location' is what appreciates. If you are lucky this could average 20% a year. If you are unlucky it could be negative. So on average housing prices grow slightly faster than inflation because the building itself is growing at about the rate of inflation, and location(land) is a limited resource so on 'average' it is appreciating faster than inflation. When I purchase property I assume it will grow with inflation. Its a 'use asset'. You live in it. It saves you from having to pay rent, and it forces you to save(through principal payments) but I don't go in expecting a ton of long term appreciation. Doing that is what got us into the housing bubble.
On that note it sounds like paying off those student loans is your best bet.