The first obstacle that stood in your way can be intercoms. Here are two solutions to the problem: to expect a tenant house that will warmly invite you into the entrance or dial casual flats and ask them to open the door (just think in advance what you can tell your subscriber - submitted by courier, a postman, a plumber, forgetful neighbor, etc.). There are also porches equipped with combination locks. This obstacle easier previous. Carefully look closely to the buttons – often those that are hit more often, have more smooth and polished surface.
If you are extremely brave and not afraid of heights – use this emergency stairway. For safety grab rope for insurance. And only not to look down.
The last failure, when you already went to the entrance and climbed to the top floor, can be a castle, hanging on the attic door. Don't worry, pull yourself together, analyze the situation and look a little closer. It may happen that the lock is hanging ajar on only key only, or close any loophole. Never need to throw started halfway.
Finally climbing closer to the sun or the stars, depending on your chosen time of day, behave with extreme caution. Try to go for joints of sheets, so as not to attract the attention of neighbors below, and keep possible for something (with the exception of the wire).No noise, no littering, do not come close to the edges of the roof, refrain from drinking alcoholic beverages, use of narcotic drugs, and do not throw down a different litter. It's not good.
But a lot of pleasant to spend this time with advantage, well, or happy. You can admire the beautiful view of the city, salute, stars, take photos, sunbathing, daydream and a lot more good.