Do u guys keep backup stock outside amazon?

I run a pet accessories brand on Amazon US, stuff like collars and bowls. Sales are pretty stable, around 40 to 60 orders a day, but inventory planning still stresses me out more than anything!!

Had one weird week a few months ago where one product got posted by an influencer and sales jumped hard outta nowhere. Almost ran out and it made me realize how little backup I had if smth random happens. Been checking warehousing companies

But I wanna ask first if having extra stock outside Amazon makes things easier or just more complicated? HOW much more complicated are we talking?