How do I determine if it makes more sense to pay PMI upfront?

[Lucas Mills]

I am looking at a 115k property for which the PMI would be $40/month because I'm putting 5% down.

On one hand, I could pay the PMI up-front for about $3,300 and increase monthly cashflow by $40, as well as save about $1,500 overall ($40 x 10 years is $4,800).

On the other hand, I could pay the $40/month PMI for 10 years and have $3,300 more RIGHT NOW which I could then presumably put towards acquiring another property and expedite that process.

So, what's the best way to analyze this given my goal of wanting to achieve 3k in passive income in the next 5-7 years?

My instinct is to pay the PMI up-front to both save money over the long term as well as increasing my monthly cash flow by $40 over the next 10 years (after which it wouldn't matter anyways because it would have dropped off).

Which option gets me to my goal faster, and why? Are there any rules of thumb when it comes to whether or not to pay PMI?