Single-family homes and multifamily properties both have their pros and cons. Single-family homes benefit from a larger buyer pool, appealing to families and owner-occupants, which makes them easier to sell. They also tend to have lower tenant turnover and simpler management. However, vacancy means covering 100% of the expenses.
Multifamily properties almost always generate higher cash flow due to multiple income streams, which also reduces the risk of vacancies. They make it easier to scale your portfolio and build wealth.
That said, the fewer units a property has, the easier it is to manage, so smaller multifamily properties can offer a good balance between cash flow and simplicity. Multifamily properties do require more management overall and typically appeal to a smaller, investor-focused buyer pool.
At the end of the day, you can be successful in both asset classes and they go hand-in-hand. I would base the decision off of how good the deal is from both an equity and cash-flow standpoint.