Classified Sites Ranking on Page 1

[TP_Marketing]

How is it that Craigslist, and Backpage get a boost from google and take over 1 or more of the page one results in my niche? Ive also seen people ask a yahoo question, and answer with a link to their website? Are these just temporary boosts?

[Igal_Zeifman]

These are pretty "strong" domains we are talking about with enormous link profiles, tons of social signals, a lot of visits etc.. You can probably "beat them" at some niche KW, but this will take some work.
This is somewhat like competing  against Wikipedia, which dominates a lot of niche KW and some major KW too...
As to your second question, permanent links will provide permanent value.

[TP_Marketing]

So will these eventually lose position since they are just a classified post?

[Igal_Zeifman]

Not necessarily.  Can you provide a link to Google SERP so I can answer this accurately?
Sometime (pretty often) Google will show one page but provide the rankings due to another page.

For example, I have a strong "CCTV Cameras" category page and under I have a "[Specific Type of CCTV Camera] " page. The first page is strong and he will provide me with high ranks but it dosen't mean it will be show for it. Instead, due to visitor data or/and social signals, the second page may appear if it's temporarily more popular.

After it gets removed (i.e. sold out) the first page, or other trendier topic related page, will assume the position.

This scenario can be discovered by looking at 100 results (use. advance search) there sometimes youll find several results from the same site, side by side - where in basic search youve saw only one single result. This is a symbiotic relationship I`m talking about. The 1st and displayed result is not the "cause" for high rank, it just "riding co-tails" of other strong pages.

From what you`ve described, you see some of these too ( " take over 1 or more of the page one results in my niche...") For these, if the 1st page gets removed, another will probably take its place...