That acronym is used as a ratio to determine if a loan would cash flow to qualify." 

Given the fluctuations in interest rates, how do you determine if a private money lending option is worth pursuing for your real estate deals?

There are multiple factors that go into determining rents and if there is limited data the rents will be off. 

Coming out of the city council meeting I determined to sell everything within the city limits as soon as it was expedient to.

If not, evict, the same way you evict any tenant.NO, you do not determine how much sec 8 is going to pay, it's based on the FMR and in some cases they pay more. 

Looking to purchase one and struggling with the right calculators to determine the real metrics.

How much of the S8 rent is covered by the program and how much is the tenant's responsibility is dependent on how much money the tenant makes.The housing department has a formula they use to determine the voucher mix.

A good sit-down conversation with the tax professional should shed some light on the topic and help you determine the next steps.

You can also ask the tenant to sign an estoppel, which essentially has them verify the rent they are paying.As for expenses, the main areas where they can go awry include property taxes, which you can determine on your own; the mortgage, which you can also calculate; insurance, for which you’ll have a quote beforehand; and utilities, for which you can obtain the bills from the landlord.

As Michael said, it depends on if you got to the level of a trade or business when it comes to lending.Some important things that will determine this are1) The amount of loans you are originating on an annual basis2) What your intent is when forming this partnership3) The value of the loans you are originating compared4) etcBest of luck