Can we use private financing to buy real estate?

In theory, yes.  In practice, not really.  The odds against private financing are substantial.  In 1997, according to the NATIONAL ASSOCIATION OF REALTORS®, 74% of all first-time home buyers obtained financing from mortgage companies, 19% from commercial banks, 1% from Saving & Loans, 1% from “other” sources, 1% from credit unions, and 1% from private investors.