In Bender v. Bender, 123 Ariz. 90, 597 P.2d 993 (App. 1979), Mr. Bender purchased a trailer park in his name during the marriage as his sole and separate property and his wife, Mrs. Bender, signed a disclaimer deed renouncing any interest in the park. Id. at 92, 597 P.2d at 995. Mr. Bender later sold the park. Id. During the parties' dissolution proceeding eight years later, the family court held that the balance due on the sales contract from the buyer of the park was Mr. Bender's sole and separate property. Id. On appeal, this court rejected Mrs. Bender's contention that the family court erred in its ruling. Id. We reasoned that married couples are free to determine the status of their property, and the disclaimer deed constituted a binding contract that must be enforced in the absence of fraud or mistake. Id. at 92-93, 94, 597 P.2d at 995-96, 997. The court acknowledged the principle set forth in In re Sims' Estate, 13 Ariz. App. 215, 475 P.2d 505 (1970), that spouses may convey separate and community property interests between them but only if done by a written instrument accompanied by contemporaneous conduct indicating an intent to convey such interests. Bender, 123 Ariz. at 93, 597 P.2d at 996. The court determined that Sims' Estate did not apply, however, because Mrs. Bender never had an interest in the trailer park to convey in light of her disclaimer at the time of acquisition. Id. at 94, 597 P.2d at 997.