May 16, 2017 · Neighboring Idaho collected the largest chunk of its tax revenue, 29 percent, from property taxes. Another 26 percent came from sales taxes and 25 percent came from an individual income tax. The state also has a corporate income tax, which made up 4 percent of revenue collected in 2014. An Idaho residential purchase and sale agreement is a legal document created by two parties involved in a residential property transaction. The individual selling the property (seller) and the individual interested in purchasing the property (buyer) will negotiate a price and, with aid from agents/realtors, will negotiate the terms that are to be included in the purchase and sale agreement.