Gentrifiers vs. social preservationists

I find Brown-Saracino's distinction between social preservationists and gentrifiers fascinating, and it both puts into words and helps explain some observations that I've had in my neighborhood at home and in Memphis. Whenever I have observed the gentrification process of a community (like the Munjoy Hill area in Portland, ME that Brown-Saracino described -- which is about a mile from my own neighborhood), it seems that there is a conflict between the social preservationists and gentrifiers, typically over space. The gentrifiers seek redevelopment of space, with some exceptions for historically significant buildings. Social preservationists seem to be more concerned about the "old-timer" residents, yes, but while presumably taking the old-timers' concerns into consideration, the way that the social preservationists define who is an old-timer can complicate the situation. 

For instance, like Brown-Saracino mentioned, Munjoy Hill was populated by white working class families as well as Sudanese and Somali families, many of whom had come to Maine with refugee status in the 90s and early 2000s. When gentrification really kicked into gear, who would be considered an "old-timer"? Whose space and livelihood would be considered authentic and worth preserving? The white middle class families had lived on "The Hill" for generations, and family names are well-known by the community. The African families, on the other hand, were more recent additions to the neighborhood scene. Their close-knit ties to each other, the schools, and community services as well as their own local businesses had quickly established a strong connection between these families and the Hill.  I don't really know the answer to this, but as I question the process of gentrification of Munjoy Hill, I venture to assume that if old-timers' needs were taken into account, it was those of the white working class families. I do know that now, a majority of Somali and Sudanese families live outside downtown Portland, far from resources, in a secluded area of public housing. 

These readings, along with many we've read for this class so far, were very frustrating to process and reconcile. The major question I'm left with is: how can social preservationists and gentrifiers, who must mean well, ensure that all their pioneering and preserving does not hurt or displace anyone who had ties to the old community?