Is foreclosure only resort?

Posted by mortagage company for the current people living in the home. The problem is that the people in the home have quit making payments. Three months ago, they wrote a "hot check" but made it good the following month, but haven't paid since. They are now 2 months behind. What recourse do my in-laws have? Must they force the home into foreclosure and sell it on the courthouse steps, or can they simply evict the current "homeowners" for non-payment and get their house back. They want to sell the house outright to someone who will get financing, and not have to deal with someone making (or not making) payments each month. Thank you!
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