20 Year vs. 30 Year Mortgage?

[Charles Liu]

So, I'm looking into my options for purchasing a rental. When it comes to financing I don't know if I should pick a 20 year mortgage or a 30 year mortgage. Everywhere online and on youtube tells me to get the 30 year mortgage because "cash is king," but in my case, the 30 year mortgage will only get about $200 extra dollars a month in cash flow (also people really only compare the 15 vs 30 year mortgages). And the arguments for a 30 year mortgage go on and on, such as flexibility, my money won't be dead money stuck in equity, etc.. However, people close to me that currently invest in rentals have told me to stick with the 20 year mortgage, arguing the extra cash flow really isn't that much, and that I'm closer to reaching the point where the rental has paid off it self and the rent I'm collecting is essentially all net. Any thoughts on this? The rent for the property will also be able to cover either mortgage, I guess it's just a matter of extra cash flow.