A$.$ Karolina and Jackson bought their Del Mar house in $2000$ for $$2,000,000$ to be used as their residence. Karolina paid $$500,000$ and Jackson paid $$1,500,000.$ When Jackson died in a surfing accident in January of $2024,$ the Fair Market Value $($FMV$)$ of the house was $$7,000,000.$

Answer the following questions depending on Karolina$$s and Jackson$$s relationship and title holding. Make sure that each scenario $1.-4.$ has a$.$ and b$.$ and possibly c$.$ answer.

a$.$ How much is included in Jackson$$s estate? Please show your calculations.

b$.$ What is Karolina$$s new basis? Please show your calculations.

c$.$ Only applicable to problem $1$: What is Jackson$$s daughter$$s basis?

$1.$ Karolina and Jackson are brother and sister, and they took title as tenants in common $25\%-75\%.$ Jackson$$s daughter is a beneficiary of his share. Karolina keeps her share.

a$.$

b$.$ Karolina$$s basis:

c$.$ Jackson$$s daughter$$s basis:

$2.$ Karolina and Jackson are husband and wife, and they took title as joint tenants with the right of survivorship.

a$.$

b$.$

$3.$ Karolina and Jackson are husband and wife, and they took title as community property with the right of survivorship

a$.$

b$.$

$4.$ Karolina and Jackson are friends, and they took title as joint tenants with the right of survivorship. Assume that Jackson had other assets and his estate will be subject to $40\%$ estate tax.

a$.$

b$.$

B$.$ In problem $4.$ above, the attorney dealing with Jackson$$s estate realized that Jackson left a will stating that his daughter is to inherit his half of the Del Mar property that he held jointly with Karolina. Please indicate who will inherit Jackson$$s share of the property and explain why.