The most expensive ZIP code in New Jersey isn't where the 'Real Housewives' live—it's here

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The median home value in New Jersey is $313,100, nearly one and a half times the national average of $213,146. But in certain parts of the Garden State, average home values can reach 10 times that amount.

That's according to financial website GOBankingRates, which collected median home values and mortgage data from Zillow, as well as Bureau of Labor Statistics-based cost of living data for 48 states and the District of Columbia, in order to identify the nation's most expensive ZIP codes. And, according to the findings, the most expensive ZIP code in New Jersey might not be exactly where you think.

While Franklin Lakes, home to some of the stars of Bravo's "Real Housewives of New Jersey," boasts average real estate prices of almost $1 million, the state's most expensive ZIP is actually 07620, part of the borough of Alpine, where the average home could cost you more than $3 million.

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"Alpine, N.J., has a median home value of over $2.6 million, by far the highest in New Jersey," says GOBankingRates. "The cost of living in this ZIP code is close to five times the U.S. average, while its average mortgage payment is almost $12,000 per month."

To calculate exactly how much you'd need to earn to live there comfortably, GOBankingRates uses the 50-30-20 budget rule: 50 percent of your income would be used to cover necessities, 30 percent is discretionary income and 20 percent goes to savings.

"Monthly costs were totaled and multiplied by 12 to get the annual dollar cost of necessities in each ZIP code," writes GOBankingRates. "This dollar amount for necessities was then doubled to find the actual annual income needed to live in the location."

Zillow Home Value Index for 07620. Data through Apr. 30, 2018.

Based on that data, here's how much to costs per year to live in 07620:

  • Necessities: $165,378
  • Splurges: $99,227
  • Savings: $66,151
  • Total income needed: $330,756

Home values in 07620 have gone up more than 5 percent over the past year and Zillow predicts they could rise nearly another 5 percent within the next year.

If you're looking for a home, experts suggest making sure you're ready to transition from renting. Here are some tips to help you get started.

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