[Closed] Can you sell your house and buy it back yourself for less?

After a 'late' night discussion - looking at if this is legal/possible....elderly relative has an equity loan against what was a mortgage free house taken out 12 years ago for a new car/travel etc (lots of old people have fallen into this). This loan grows exponentially as they do, to a frightening amount compared to what the original loan was. She can't get booted out even if she lives donkey years but one day in theory this growing loan could take up the whole value of the house and no inheritance for relatives.

So the options are; stay put do nothing and the above happens. Swap to another loan company at a lower interest rate and the loan still grows but not so fast. Sell up, pay the loan off and move somewhere smaller. A mixture of selling up, paying part of loan off, and moving somewhere a bit smaller but with still some loan outstanding.

Or, could you sell the house for market value but somehow she/relatives then buy it back but at a much reduced amount i.e. enough less to have wiped out the loan. She then stays put and debt is gone. Seemed simple in theory after a few beers.
Any thoughts? Need legal/independent financial advice I know.