joint with survivorship income tax implications

[RB41]

My Mother purchased this property in 1959 for $9,500. At some point with a warranty deed she put my oldest brother on joint with survivorship. Then
in the 1974 with a warranty deed, my mother and older brother put themselves and three other siblings names including me) on the property, joint with survivorship and then one sibling passed in 2011 (oldest brother), my mother passed (February 2020), we sold the property. 
. Is it a purchase, or inheritance, or a gift? I'm trying to run the numbers through my 2019 Deluxe turbotax to see what my tax implications would be but it's too cut and dry; nowehere to put money spent on improvements since 1974.

[Opus 17]

You may need to have a tax professional review the deed.

In most cases, if you are a "remainder man" (or person), meaning you are a co-owner but someone else has a right of survivorship, that means you really aren't given anything of value until the person dies.  (You couldn't sell your share of the house to a stranger, for example, while your mother was alive.)  So the IRS considers that you inherited the property when your mother died in February and you would receive a stepped-up basis.  The you and your siblings would report the sale as whatever your share of the sales price, and your basis is the same  as the sales price, and you won't have a capital gain.

However, you may want to have someone review the deed in light of your state laws on property ownership to make sure the deed was prepared correctly.  If not, you really will have a mess figuring out your basis.

[tagteam · Accepted solution]

If you, and your siblings, were actually placed on the deed as joint tenants with rights of survivorship (JTWROS), then as each joint tenant dies, the remaining joint tenants acquire the deceased joint tenant's interest by operation of law. As a result, you need to know the fair market value as of the date of death of each joint tenant who has passed.

As @Opus 17 stated, however, you should seek professional guidance with respect to this scenario.