Hi there Hermanth, many of the most desirable communities in Union County offer the advantage of access to public transportation and well regarded school systems. I've found that with the market corrections, many of the buyers I have worked with recently have been steadfast in their desire to buy a home with access to public transportation and Union County communities offer this. Those communities that also offer great schools and a nice downtown area are in demand.
Of the communities you mentioned, I think that Cranford would be the least expensive. Another community to consider would be Mountainside. In Morris County, I'd suggest Morris Township, there you have the advantage of being close to Morristown, one of NJ's great metropolitan/suburban towns, along with Westfield and Summit. Another Morris County community to consider is Long Hill Township which feeds into Watchung Hills High School (oddly along with Somerset County"s Warren, Watchung, and Green Brook). In Middlesex County, I'd suggest you consider Piscataway and Edison. Depending on your price range, and commuting requirements, there are many options to consider.
If you'd like to discuss further, I'd be happy to provide further guidance.
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Prices have corrected everywhere, including in Union County. What I am seeing is that the "time to sell" is quite brisk in Union County. This reflects the healthy demand due to the factors I mentioned. These very factors will be a positive when you go to sell as well.