With a commercial property (office/retail/flex etc.), you have the opportunity to make more than you do with a residential investment. On average, commercial investors achieve an annual return of about 6-12%, whereas residential investors usually see smaller returns.
And with commercial you may have longer vacancies, but the tenants are far more likely to sign a long term lease. My first investment property is commercial and 3 out of 4 tenants are on 5 years leases, but one office was vacant for 13 months.
There's also less drama with commercial tenants than with residential tenants. Having said that, I'm looking at buying a residential property in 2018 to diversify my holdings.