Methods are provided for real estate investment, development, and ownership. The methods allow multiple users to combine their resources to purchase, make improvements to, and individually own and/or sell real property. The users save money or realize greater profits on real estate transactions by taking on the roles of upstream investors, developers and real estate agents. In one embodiment, undivided interests in a real property are sold to a plurality of buyers. The buyers each pay a portion of a cost for making an improvement to the real property. In one embodiment, the buyers only pay a guaranteed estimate for the improvement costs. Upon selling the undivided interests, each buyer also reserves one or more portions of the real property. When the improvement to the real property is complete, sole ownership of the reserved portions are transferred to the respective buyers. In one embodiment, the buyers receive a discount for referring other buyers that also purchase an interest in the real property.