>So the amount of homes in the DB is the most important factor?
The rule is the same as everywhere else: "useful unique content." That rule would work out differently in each category.
For a directory I always ask, "can I (as ODP category editor) best provide content for the user by simply listing everything that directory does?" If the answer is "yes" -- I do. If the answer is "no" (either "I don't have time right now" or "they're adding sites so fast I wouldn't keep up" or "they have good content that doesn't fit the ODP data model") then I list the directory, as well as possibly some of its content.
Number of homes counts as "quantity of unique content." If I click on three links and two are dead, I'm not likely to list it.
Uniqueness counts. Can our users find most or all of the listings in directories that are already listed? If so, we'd be doing them a big disservice not to reject a site.
Usefulness counts: can the editor quickly get in and get a feel for how much content there is, or do they have to go through a Spanish Inquisition of irrelevant personal queries?
Concept counts. Are there other directories that serve this same niche?
Obviously, this site has at least two strikes against it already: maximally-non-unique concept, and absolutely-minimum content. The editor needs no further reason to reject it and go on to review some more promising site.
Now, could you change the site enough to force the editor to look for another strike? Probably. Could you add enough content to make it worthwhile for our USERS to have Yet-Another-Expletive-Deleted-Classified-Ads-Page-For-Vacation-Rentals-In-Orlando?
Possibly. But ... "Rising bar for directories", remember?
Aside: You know how commercial webmasters (understandably) always want the ODP to review their commercial sites instantly? And they propose all sorts of half-baked schemes to accomplish that. But the fact is, the ODP does pretty much what it is able to do using its social structure and support commitments, and doesn't do any more. People can want whatever they want, but a fundamental change would require starting from scratch. That's just life -- and not just for the ODP; other websites have constraints of the same nature. For instance (getting back to the point) this website has strong evidence of a distinct lack of significant content-collection commitment....and that isn't going to change, either, just because some outsiders (like users or even ODP editors) want it to.
So: my money is on "this site is an eternal reject" -- not because it doesn't have enough content (that could change), but because it doesn't have enough content-collection capability (which probably won't change.)