A right of survivorship means that property owned by multiple people will automatically pass to other owners when one owner dies.
As part of the recent budget passage, New York State adopted legislation that allows for Transfer-On-Death (TOD) deeds pursuant to N.Y. Real Property Law §424.
Tenants in common gives you more protections and you can specify in a deed of trust what you would want to happen in the event of relationship breakdown (eg if one of you has first dibs to buy the other out, or a time limit on doing so etc) which is definitely better to decide now whilst you still like each other!
Common ways to hold or transfer property to avoid the New York probate process include: Living trusts. The State of New York allows residents to create a living trust for nearly any type of asset, including houses, properties, vehicles, and bank accounts. Co-ownership. Beneficiary designations.
To sum up: Joint tenants must receive their property interest simultaneously and from the same source with an equal share and equal rights to possess the entire property. By contrast, tenants in common can receive their interest at different times and from disparate legal sources and don't have to possess equal shares.
Real property New York recognizes tenancy by the entirety for real property conveyed to the spouses, unless there is documentation that another form of ownership exists.