1031 Exchange towards a primary residence

[Stuart Powell]

My parents are selling multi-unit (10) apartments, which is part of an LLC. The LLC consists of my parents and a family member who recently passed away, and the property is fully paid off. When its sold, can the funds be use to pay off their current primary residence with a 1031 exchange, or can that money only be used towards the purchase of new properties?  My mother is retired, and my father still works (but would likely want to retire in the next few years, so cash flow w/ new rentals would be my recommendation vs. paying off the mortgage if that's an option). If you were in their shoes, any recommendations on what you would do with your portion of the sale?  Is seller financing an option to consider?

Also with the 45-day rule, that seems like a short amount of time to sell a property and buy a new one. Do most people just have to make quick buys after their property is sold? Any work arounds or tips to know for 1031 exchanges?

Greatly appreciate your advice!