I have few queries regarding IT.

1. Can you provide comparison of old regime or new regime for Min 20 lakh salary?

Ans: 01. First of all, calculate LTCG on this transaction, considering Sale Value & Cost of purchase. You both shall file your ITR on the basis of 50% share of LTCG each.
02. If you purchase Capital Gain Bonds, these should be taken separately in the name of both of you. However, spouse can be a co-applicant, while purchasing these bonds or nomination in favor of your spouse can be made, to protect your interest.
Most Welcome for any further clarification. Thanks.

Ans: Get GST number based on your place of work. Issue proper Invoices for all transactions, which may be in any State of India. Don't forget to charge GST on the same at applicable rate & then deposit the GST with the department. You will also have to file proper GST Returns, which are applicable in your case.
Most Welcome for any further clarification. Thanks.

Ans: It is always better to avoid yourself in getting involved in such transactions. IT Department may doubt these transactions. Once in a while for small amount, it is O.K. BUT never on regular basis.
Advice your friend to get the amount transferred in his account directly online & he should disclose such income in his ITR.
Most Welcome for any further clarification. Thanks.

Ans: Yes. She can sell her property & purchase a Residential Flat in Mumbai, in the name of her daughter & claim Exemption u/s 54. However, department may raise some questions in such cases, which you may have to face. There are some cases also which will support your argument.
Another option is to purchase the property in the name of your mother in law (or joint names of both mother & daughter) & get her (mother in law) WILL Registered, in favor of your daughter. This will not create any problem while transferring the flat in favor of your wife later on.
Most Welcome for any further clarification. Thanks.

Ans: In your instant case, your tax liability is subject to ADVANCE TAX. Kindly compute your tax liability accordingly & then match the same with the calculations of the department. I hope, there should not be much variation in these figures.
Most Welcome for any further clarification. Thanks.

Ans: Yes. Any Gift received from Father in law, is not your income but gift. Hence, it is not subject to income tax.
Most Welcome for any further clarification. Thanks.

Ans: It can easily be done if you have got WILLS of your Grand Father & Mother.
First your G/Father's share will be transferred in favor of your mother, on the basis of his WILL & then, your mother's share can be transferred in your favor, again on the basis of WILL of your mother. Both WILLS should be Registered.
Most Welcome for any further clarification. Thanks.

Ans: Dear Anonymous,
I am sorry but I didn't get you. Are you in a long distance relationship with a 35+ woman? Or do you want to marry someone who's 38+? I am a little confused. I need a little more clarity to help you with this.
Best wishes.

Ans: Advisable to contact placement agency to check if there are placement opportunities. At 51 years getting placed is difficult. But if you are willing to get a lower salary you can get a job.