I won't sugarcoat the New Jersey tax reality, and Union County carries a real burden, so let's use the number that matters.
The honest figure is the bill, not the headline rate. Rahway's median property-tax bill runs around $9,700 a year, so a typical home lands in the low-to-mid $10,000s, and a condo often runs less because it's a smaller, lower-priced piece of real estate. On Staten Island a similar-priced home runs closer to $5,000 to $6,000, so plan on the bill rising, roughly doubling on a house.
Here's the honest framing: that bill funds the schools and the city services, and in a condo the math is friendlier because the unit's assessed value is lower. Run the real, settled number on the specific home or unit, and if it's a condo, factor the HOA alongside it, together they set your true carrying cost.
What I do about it: before you fall for a place, I pull the actual tax bill and, for a condo, the building's HOA and financials, so you see the full monthly, taxes, fees, and all, not just the list price.