and I'll try and answer your basic question;
whether this is a good thing ( and ) would that be a sound investment?
I am by no means an expert on Real Estate. I have never bought a home (and I am 53) and have only rented.
But I know Bonds.
So lets consider this entire scenario as if it was a bond.
If you buy a 30 year Treasury, you will need a coupon or at least a yield of 3.33% to realize a doubling of your money. In other words, if you paid "Par" ($1000.00) for the bond, and it had a coupon rate of 3.33%, you would receive $33.30 per year in interest. Over the course of 30 years, you would get $1000 in interest payments and when the bond matures, you get your grand back. You doubled your money.
In the case of a 20 year note, the yield or coupon would need to be 5%.
OK?
So what you are suggesting is basically buying the bond, giving it to your brother and have him pay you a set amount for a specific period of time in order to pay you back for the initial purchase cost. After that he is going to give you the coupon payments. You also are going to set up this account so that it has a "Transfer on Death" provision. You guys die, your brother gets the bond, he keeps the interest payments and when it matures, gets the grand.
Does this NOW sound like a good "investment"?
Well.....no, not to me, anyway.
What happens to the house when the note is paid off?
How long will your brother live there?
Who is responsible for repairs and upkeep? You guys? That is how it works, generally. If I rented the house from you, I wouldn't expect to pay for a new roof, for example. I also have no expectation the house would be mine if you kicked the bucket either.
My advice is to talk with an attorney. Perhaps you could title the house inside a trust, making your brother the successor trustee.
Depending on the laws in your state, you may be able to set up an LLC and use that entity to buy the house. The point being you would be wise to seek some legal "insulation", if you will.
The thing is, regardless of how much you trust your brother, money does strange things to people. One must tread VERY carefully when entering into transactions with family members that involve large figures.
Be careful and good luck.