Interest bearing loans & Transactions

Earning interest to pay off an interest bearing loan

Q: I have a brother and a sister. My brother has taken a loan from a bank and has to pay back the loan with interest. My sister wants to open a fixed deposit with the intention of giving the interest earned on the fixed deposit to my brother so he can pay off his own loan. Can she do it, even when my brother has enough income to pay off the loan himself?

Making taubah for taking an interest loan

Q: If a person, who in ignorance, took out an interest loan, thereafter realized his sin, made sincere taubah and made a promise to Allah never to take such loans again. However he still has the debt/loan to pay off and he doesn't have the full amount to settle it. Now going forward, does he still fall under the curse of Nabi (salallahu alayhi wa sallam), as he still has to pay off the loan and he will still be paying interest? Please advise whats the way to correct the situation.

Car dealership helping the customer acquire a credit facility with interest

Q: Is it permissible to own a car dealership whereby you sell cars to customers borrowing money from the bank and are paying interest?

From my understanding, even to witness the transaction is a sin. In this case we may be encouraging it to make a sale and helping the customer get finance. Is the profit from the sale halaal?

In some instances the banks give the dealers a kickback for arranging the finance with them, would this money be halaal?

Being a witness to signing for a home loan bond

Q: I was traveling with a co-worker who stopped at the attorney offices and asked me to come inside with her. When I went inside I was asked to be a witness on signing for a home loan bond that was taken with the bank.

I am feeling very uneasy and I would like to find out if I have committed a sin by being a witness to the interest stipulated on the contract.

Can I somehow get my name removed from that contract as I myself try my utmost to not deal with interest bearing loans.