And how sensitive is that to interest rates changes (the rate you brought at vs the rate the new buyer can get in the market when you want to sell?)

Although not as sensitive as hardwood to temperature, humidity and sunlight, these things still effect LVP.

@Kevin Hoover, these are good lessons and the one that I want to highlight is: "interest rate sensitivity makes the model a gamble, not an investment".  

These items are not permitted to biodegrade in traditional septic systems.Plumbing pipes are sensitive and must be checked regularly by scheduled plumbing professional.

Many of my relatives have been born, lived and died in that house over the past couple centuries, and everyone who's been there that's sensitive to ghost activity has told us it's haunted.

If there's a hole, it may be a red flag.b) sensitivity analysis: I examine all the assumptions, and make sure I can live with the worst case scenarios.c) "Stall and see": if they are getting money over multiple years, and there is no penalty for investing later, I would usually wait so I get some real performance data, versus having to look at theoretical pro forma information.d) Recession stress test: I will not invest in anything, until I subject it to recession level stress and see if I can live with the result.

He has stellar credit but is unable to make deals due to the sensitive financial company he works for and the amount of student loans he cosigned for his kids. 

But if your buying existing seconds these safeguards wont exist these have to be new origination. 

BUT, can Google or books answer you within hours of your time sensitive question?

If there's a hole, it may be a red flag.b) sensitivity analysis: I examine all the assumptions, and make sure I can live with the worst case scenarios.c) "Stall and see": if they are getting money over multiple years, and there is no penalty for investing later, I would usually wait so I get some real performance data, versus having to look at theoretical pro forma information.d) Recession stress test: I will not invest in anything, until I subject it to recession level stress and see if I can live with the result.