In the real estate world, raising capital from investors to fund the equity portion of the acquisition is incredibly common.
The investment (often called syndication) is generally structured where the investors get (1) profit share, (2) preferred return, or (3) interest rate. After paying expenses, setting aside reserves, and calculating what the investors receive, the sponsor (often called manager, general partner, promoter, etc.) receives any remaining cash.
There are a lot of technical requirements for raising money from investors and you definitely should speak to a qualified securities attorney before accepting investments. Generally, your regular or real estate attorney doesn’t have the specialty knowledge of the intricacies of options for getting your deal funded with “other people's money”.