Hi,
Ans:-1 The Reply to your Question is as follow:-
1.) Your arrangement is legally valid. You have to include this value in your Income Tax return as exempted income.
2.) There is no lock in period as such to be maintained after the gift deed is executed and before the sale of the house also.
3.) The Capital Gain exemption is only allowed in case of Sale of Long Term Capital Asset. To qualify as a long term capital asset we need to check the period of holding and Explanation 1(b) to section 2(42A) of Income Tax Act, 1961 provides answer to the above situation. It says that in the case of a capital asset which becomes the property of the assessee in the circumstances mentioned in sub-section (1)]of section 49[ie in case of gift or inheritance or liquidation of a company or under irrevocable trust], there shall be included the period for which the asset was held by the previous owner referred to in the said section. So in your case even if after gift you sell the asset same day then also you are eligible for exemption.
Further, You can claim the exemption under Section 54 of Income Tax Act,1961 by investing in another residential house property and with effect from A.Y. 20-21 the benefit of exemption is extended if it is made in two residential property instead of one earlier. Also Important to note here is that exemption is only available if the Long term Capital Gain does not exceed ₹2 crores.
4.) Yes, the sale agreement will be in the name of all four sellers who will be presently holding that residential house since, only then the house will be transferred fully.
5.) Conclusion:- You can sell the Residential house after executing gift deed even same day after transfer and Long term Capital Gain will arise after indexation benefit to you(Please reach out if you help in calculation, since it can be only done after having values in hand).
Ans:-2 in case of sale oh house in Oct/Nov in 2020-21, this transaction is to reported in Income tax return filed for the A.Y. 2021-22 i.e. FY 2020-21 and not in A.Y. 2020-21 i.e. FY 2019-20