While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking analyst upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Goldman Sachs resumed coverage of office REIT Boston Properties (NYSE:BXP) with a buy rating, suggesting that Friay's 1.5% pullback might be a decent buy-in opportunity.

So what: Along with the bullish call, analyst Brad Burke planted a price target of $130 on the stock, representing about 15% worth of upside to yesterday's close. While contrarians might be turned off by Boston Properties' rise in recent months, Burke thinks there's more room to run given his view of continued development improvement and strong lease rates from its high-quality assets.

Now what: According to Goldman, Boston Properties' risk/reward trade-off is pretty attractive at this point. "Underperformance appears overdone (4% under the RMZ over the past two years) as market conditions continue to improve around large development projects like Transbay, and investors have greater visibility on the long-term composition of company management," Burke said . When you couple that relatively poor price performance with Boston Properties' strong revenue and FFO momentum of late, it's easy to understand Goldman's bullish stance.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.