With the arrival of the boxes coinciding with the year-end tipping season, that good cheer can translate into welcome cash.

"Wow! Look at all these boxes!" said doorman Ray Flores, 56, with a big grin as he waded through packages stacked thigh-high in the mail room of The Normandy, a 257-apartment building on Manhattan's Upper West Side.

This year's early holiday buying frenzy started with a bang as shoppers rang up nearly 17 percent more online sales on so-called Black Friday, compared with last year, and 30 percent more on so-called Cyber Monday, the biggest internet purchasing day in history .

Laden with those purchases, fleets of United Parcel Service vans, FedEx Corp trucks and United States Postal Service vehicles are pulling up to city buildings to disgorge their haul.

The daily load won't lighten until the last wave of unwanted gifts is returned in the new year.

"In the past few years, it's increasing and increasing and increasing, and this year, it's way up," said Michael Crespo, 65, a doorman at the Dorchester on the Upper West Side, where he said daily deliveries have quadrupled in the past week.

Around the corner, doorman David Morales, 38, said deliveries have doubled since the holiday buying began.

"It gets messy," said Morales, saying the mounting deliveries will soon spill out into his usually tidy lobby.

"If it rains or snows and they're wet, that's worse," added Billy Roman, 46, doorman at The Clarendon nearby, where he said deliveries have increased 60 percent in recent days.

Christmas morning is still weeks away, but gifts in the U.S. city with the nation's largest Jewish population are already pouring in for the start of Channukah on December 8.

"How many days do they have to get presents - eight?!" said Roman.

In the most recent year-end tipping season, 25 percent of the apartment owners in doorman buildings reported handing out tips of $1,000 or more, compared to 10 percent of renters in doorman buildings, according to a 2011 survey conducted by brickunderground.com, a New York City real estate website.

The year-end gratuities come on top of the average $20.76 hourly wage earned by the city's 12,800 doormen, concierges, porters and elevator operators, said Maia Davis, spokeswoman for 32BJ, the largest building workers union in the city.

Some doormen said they are confident that apartment dwellers recognize what a big impact the click of a mouse can have on their building doorman's daily duties.

"The residents say, 'Hey Ray, you got a lot of work,'" said Flores, straightening stacks of boxes from Amazon.com, Zappos.com and other online shopping sites.

"I say, 'Yeah, a lot of work - you ordered all this stuff!"

Still, some 61 percent of apartment renters don't tip their doorman, superintendent or building staff, according to a survey sponsored by Rent.com, a rental listing site. (Editing by Ellen Wulfhorst and Andrew Hay)

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