Are Unreal Property properties listed with other sellers/referrers?

Yes almost always. Developers rarely give one agent exclusive rights to sell a project. Frequently, developers may sell a few themselves if they are big enough to have a sales team and depending on the size of the development, may have up to 10 different groups selling the property. In their financial projections, developers frequently allow for a cocktail of selling arrangements at differing rates of commission and differing marketing budgets.