With its acquisition of GGP finally complete, Brookfield Property Partners is about to begin the more difficult task of turning its properties around.

Brookfield officially took full ownership of GGP in July in a deal valuing the mall-owning REIT at $15B (before then, Brookfield owned a 34% stake in the company). It has since begun the process of bringing in equity partners in many of the malls it acquired, with different goals depending on how well each center is performing, the Wall Street Journal reports.

For the better-performing malls, Brookfield will be adding stores and updated concepts. For the struggling properties, it will be either shrinking footprints or introducing mixed-use elements like apartments or hotels, the WSJ reports. The plan is similar to what Brookfield executed after acquiring Rouse Properties in 2016.

A key difference is the creation of a new REIT to manage the 125-unit portfolio that GGP brought with it. Brookfield Property REIT will be listed on Nasdaq and managed by Brookfield Asset Management, Brookfield Property Partners' parent company. The REIT will attempt to bring in partners and additional equity to redevelop its struggling malls before considering any sales, Brookfield Property Partners CEO Brian Kingston told the WSJ.

Brookfield has already sold about $4B in equity across the GGP portfolio to bring in joint venture partners, but its strategy isn't popular with many of the GGP shareholders who have been presented with the choice to receive $23.50, one share of Brookfield Property Partners or one share of Brookfield Property REIT in exchange for each GGP share acquired by Brookfield.

Those shareholders, frustrated with the potential devaluing effect Brookfield's acquisition price could have on mall properties as a whole, have privately been exploring selling out of Brookfield to invest in other retail owners such as Simon Property Group, the WSJ reports.