1.Ukrainians are quite poor.
Despite of Ukraine to be the definitely poor state (comparably to Western Europe countries), ukrainians have the European level of life and culture. Coming to Kiev first time you will be surprised by the quantity of quite expensive cars on the streets and a number of newly build residences or even castles in suburbs. People are well-dressed and far from starving. You will not find anywhere in Ukraine scary blocks like existing for example, in Buenos Aires, even in the most remote rural places.
Somewhere on a streets you can come across scroungers, also called "bomzhi" but they are not numerous. Also Kiev - is one of the most expensive cities in the world, be ready to meet high prices in restaurants, hotels and shops.
2.Kiev is unsafe place
In fact, Kiev is much more safer place then London, Paris and New York. Street crime exists as anywhere, but on a lower degree and usually people who are not looking for troubles will be not meeting troubles. There are no crime districts in Kiev, but the center is much more adapted for night walking.
Other unusual tip is that ukrainian police better has to be looked out. At the moment, police is the most corrupted organization in Ukraine,and they will do nothing to help you without bribe but will do everything to assign your money. Be sure your documents are ok.
3.Kiev girls are available and dream about marriage with foreigners
Walking along Kiev streets you see a lot of beautiful ukrainan women, hot dressed, in short skirts, high hills and sometimes with provoking writing on the clothing. But it does not mean anything. Women just used to dress in this way - it is more like tradition or accepted style of life in big Ukrainian cities. Of course they understand the meaning of graffiti on clothes. English language is studied in schools and many people can understand it at least.
The idea of getting marriage with foreigner is not quite popular among ukrainian women. Even considering the financial aspect of marriage, avarage ukrainian man is used to spending much more of income on his woman then an avarage european. Also it is common and normal to pay for woman in restaurants or cinema or other places for entertainment.
4.Ukrainians and Russians are the same or Ukrainians hate Russians
Both above statements are absurd. Ukraine is not only a different country from Russia, but its nation, traditions and culture was formed in different historical and social situation also. Ukrainian and Russian languages are similar, every Ukrainian can easily understand Russian, but Russians usually do not understand Ukrainan language. However, coming to eastern or southern Ukraine it is better to use russian phrasebook because the influence of russian culture is quite high there.
Ukrainians never hated Russians, both nations are very close to each other and similar. There are a lot of jokes about ukrainian-russian relationships but nothing more then jokes.