Depending on how many weekends you are planning on staying, there may be some benefit to booking straight through in one hotel, getting a lower rate and avoiding the tax after 30 days. Have you talked to the GM at the Ren? If you say you want to book straight through for a long period, they can usually give you a better rate.

If I wasn't on a long term stay, I used to often switch between hotels during the week and on weekends. If you were going back to the same hotel, then you could leave most your stuff there in storage, and just take a small bag to make the transit easier.

In your search, also think about including the Courtyard Jersey City Newport. It can be a convenient location, just beside the PATH into Manhattan.

Enjoy New York.