Jack, I don't work in Indiana, but a typically contract in my area are 12-15 pages long and often longer. There are a number of considerations to make and details to attend to.
If you are not working with a licensed agent, I would encourage you to find an attorney who regularly does real estate purchase & sale work. One missed issue can cost you your earnest money, a chance to get repairs done or get you stuck buying something you didn't expect.
Even if you are buying from a family member or friend, all the specifics need to be spelled out so that the relationships are protected. Best of luck with your purchase.