Obligation of zakaat and qurbaani if one has a share in a property

Q: My father passed away in 2021 and, we, the heirs (mother, and 3 brothers, all adults) inherited property and cash as per shariah.

1.The cash was given by us to our mother. We made her the owner of that cash.

2. The property inherited (2 x 5 marla plots) are combined property of our mother and 3 brothers, the net worth of shares is above the nisaab.

Our mother pays yearly zakat as well as Qurbaani.

The question, Is it compulsory for us 3 brothers to pay zakat and qurbaani, provided that our indiviual monthly incomes/savings are less than the amount of nisaab (cannot even buy or share an animal for sacrifice and neither of us can move/sell, the shares of property, or use for any business means). Will zakat and Qurbani be applicable on this sort of shared property?

Calculating the price of qurbaani animals when making qadha

Q: A person has many years of missed qurbani that he needs to make up for by paying market values.

1. Must he use the market value of a local animal (which would be expensive) or can he use the market value of a cheap country (such as the value of 1/7 cow in India)

2. Should he use the market value for the current year, or should he use the market values for the past years when he missed the qurbanis?