"Commercial real estate, particularly retail and office real estate, is another key variable," Hainlin says.

Landlords have struggled this year to keep up with rising coupon rates on mortgages, which most recently averaged 7.21%. That is double the average rate of 3.62% in 2020, according to Moody's.

The hardest-hit commercial properties have been offices, which have experienced rising vacancies since more employees began working from home during the pandemic.

"How does that work out?" Hainlin wonders. "Do you end up repurposing those those facilities? Do people come back into the office more in full than they have post pandemic? These are key variables, in addition to the Federal Reserve and interest rates and consumer spending, that will be driving market returns in 2024."