Yes, it’s called a Back-up Offer Addendum. As a listing agent, I always like having at least one back-up offer to keep the primary buyer moving forward because they know if they push back too hard on repairs or other contingencies there’s somebody else ready to buy the property.
Having a back-up offer in place is also beneficial if the primary buyers can’t or won’t buy the property. That way my seller doesn’t lose any time by having to put the property back on the market because the back-up buyer can just slide into primary position.
Being in back-up position is also beneficial for the buyer because they can always cancel the agreement if they find another house they like better. This is why I like having more than just one back-up buyer for my listings. However, some of my buyers have been able to purchase a home because they were in back-up position and the primary buyers canceled.