NEW YORK ( TheStreet) -- Amazon ( AMZN) is scheduled to post second-quarter results after the closing bell, and once again, investors will be monitoring the online retailer's razor-thin margins and the affect of Europe's macroeconomic weakness. The Seattle, Wash.-based company has spent the last few years pouring money into upgrading its warehouses, developing new technology and improving its digital library for its electronic devices. Last quarter, for example, it acquired robot manufacturer Kiva Systems to operate its shipping centers. Although the spending has caused Amazon's revenues to surge, it has pressured the company's bottom line. Amazon's total worldwide operating margin was 1.5% during its fiscal first quarter. By way of comparison, e-commerce giant eBay's ( EBAY) operating margin was 20.5%, or 27.3%, excluding items, during its most recent quarterly results. Apple ( AAPL), which touts its iPad against Amazon's Kindle Fire, reported an operating margin of 33% in its third-quarter results on Tuesday. BMO Capital Markets expects that Amazon's margins will be in the spotlight for some time. "We expect the company to spend heavily in fulfillment centers as well as technology and content to drive this robust growth, compressing operating margins in the short term as a result of these expenditures," explained the research firm, in a recent note. Nonetheless, BMO rates Amazon 'market perform', predicting continued robust revenue growth. Amazon did not report a gross profit margin during its first-quarter results earlier this year, although YCharts estimates it was 23.95%. Apple's most recent gross profit margin, in contrast, was 42.8%, while retailer Target ( TGT) had a gross profit margin 30.2%. Carlos Kirjner, an analyst at Bernstein Research, rated Amazon 'outperform' with a target price of $251 in a note to clients on Monday. He projects 32 cents of earnings for the second quarter, "driven primarily by gross profit margin expansion." Amazon's shift to selling more of its products through third parties and the growing popularity of Amazon Web Services is seen as benefiting the company's margins. The company's mix shift is yet to be fully incorporated into consesus estimates, providing upside opportunity, according to Kirjner. After eBay and Google's ( GOOG) second-quarter commentaries suggested growth in the UK and northern Europe, Think Equity analyst Ronald Josey raised Amazon's price target from $235 to $250 and reiterated his 'buy' rating in anticipation of strong second quarter results.