<prompt> Human: My sister and her husband are looking to purchase a home for them and their two small children. Thats great but unfortunately theyre looking in Seattle, having just moved to the area. Its been tough for them to find anything in price range they can afford in the area they would like to be in. Also, its surprising how much people are willing to pay for homes that are so small in this market. My wife and I are considering helping them and are thinking about a scenario where we put a few hundred thousand into a house with them. The terms would basically be that we would retain an interest proportional to our investment so eventually when they sell the house, or wanted to buy us out, we could relatively easily determine the value of our share. For simplicity lets say they are in the market for something in the 700k range. If we were to offer a co-investment of 300k such that they could purchase a home at a 1M value we would have a 30 interest in that home. If the home were to go up to 1.3M in 10 years could be more, could be less and they were to want to sell and move or to buy us out our 30 would then be worth 390k. In this scenario its not a loan, theres no payments owed. Just the future value, or a way of calculating a present value at the time of a buyout. I was imagining terms that include, no responsibility for sharing maintenance costs, possibly no responsibility for paying property taxes etc. the benefit to them of the co-investment is that they get to live in a 1M house for as long as they want. For us the benefit is that we get to help them and they get to be in an area that they want to be in and in a decent house for the price of a less expensive house. Yes, I know we would be on the hook for taxes, maint. etc if they cant pay - thats not an issue for us. Does anyone see any major issues with this kind of approach? We would like to keep things simple. We dont have any dependence on the invested capital or any kind of exit timeframe. They can stay as long as they want and sell whenever. Thoughts? also posted in RealestateInvesting  <response>: Bad idea, dont tangle finances. There are plenty of homes for 700k in seattle and 1mil buys a really nice house. 