It has been brought into question whether the reforms mentioned above apply to the majority of rural-to-urban migrants. Specifically, many reform policies, especially those during the first and second periods, appear to require rural migrants to possess some sort of capital, either human capitals (such as professional skills and titles) or property-related capital (such as the ability to become an urban homeowner) or both. Some scholars hence also call some reform policies as ways of "selling" hukou. Meanwhile, many migrants have claimed that their lack of social networks (part of what is called “guan xi”)—which in some sense is also accumulated with wealth—also has made it harder for them to find a stable job, let alone a lucrative job. Hence, if wealth is a precondition to change from rural hukou to urban hukou, many rural migrants indeed are unable to gain that access, as many are “unskilled” (because many's skills, such as farming, are not categorized as professional skills) and poor. However, in some large cities, even if a rural migrant does carry certain professional skills, it is not a guarantee that one will be granted with urban hukou. This situation is particularly revealed from many highly educated migrants. Despite of their education background, many would not be granted with urban hukou unless they become a homeowner. However, given the high price of real estate in many large cities (such as Beijing, Shanghai, Guangzhou), many are unable to do so even if some cities do offer housing subsidies to migrants. Given their lack of urban hukou, many not only face the difficulty of purchasing an apartment—let alone purchasing a house—but also the disadvantage of being a renter. Because of the lack of rent control in many large cities, even if one rents a room—or rarely, an apartment—one can face the possibility of being asked to leave. Many those educated migrant youths hence are also called “yi zu,” literally “a group of ants,” as many do not have their own room and have to live in a tiny room with many others.