Both numbers you read are common, and neither is a rule. A syndication is a private offering where one sponsor buys one specific property and a group of passive investors funds the equity. Minimums are set by the sponsor, and 25,000 to 100,000 is the usual band, with 50,000 the most common. A fund pools money across several properties and tends to set minimums higher, often 100,000 and up, because managing many small investor positions costs the same as managing large ones.
So 25,000 will find you deals, but the pool is narrower, and you should know why. Most private apartment offerings rely on rules that limit who can invest, and many sponsors only accept accredited investors, which is a defined income or net worth test. Whether a particular offering can accept you depends on how it was structured, and that's a securities question for a licensed professional, not something to work out from a forum. Ask the sponsor directly which exemption the offering uses and whether non-accredited investors are eligible.
There's also a liquid version. Apartment REITs, meaning listed companies that own large multifamily, trade in any brokerage account with no minimum. You get diversified exposure to the same sector and daily pricing, and you give up the specific-property value-add upside that a syndication is sold on.
The part to sit with before writing a check: private deals typically lock your money for five to seven years with no way out, and in a period where values sit 20 to 30 percent below the 2022 peak, holds get extended and distributions get paused while sponsors wait for a better exit. If 25,000 is most of your savings, the illiquidity matters more than the return projection.