Hi. It really depends, newer properties tend to be higher than say an older multi family or single family home. Can be anywhere from 6k - 15k depending on when it was assessed. It has to do with the city's budget.
If you're buying new construction then I would recommend you contact Weehawken's tax assessors office directly and have him calculate it for you.
If it's an existing property I can look up for you what the properties taxes currently are. Contrary to belief, the property taxes are not adjusted with each new purchase price/transaction.