Besides that, just wanted to chime in real quick - I'd highly check in with a CPA and I am no tax expert, so wanted to preference that.

And end of year actuals never pencil out like the spreadsheet...I'm not saying that it's a bad idea; I would just urge you to proceed with extreme caution.

The money that you end up owing to repay the loan over the 5 year term is now post income tax money unlike how you traditionally are supplying your 401k with pre-tax money.  

high priced markets like west coast pricing might be 75 to 95% of note value..

If sold for the amount I want I will have 30k to 40k at the end.

You have a lot going on and if you had a 457 you were a highly compensated EE.   

Our solution is "Do all the work on the front end" - we vet the applicants internally and go through their info with a fine-toothed comb.

Since you are in an expensive market, commissions will also be high so you should be able to cover all of your expenses with just 1 deal basically, maybe 2. 

But the level of negative cash flow that you're talking about is quite high and it sounds like it's not something you're comfortable with and thus should look for something else.

Here's the problem: They are not a sustainable asset for most to own; they are difficult and costly assets to exit through a sale; if you achieve favorable refinances, you may be able to use those funds to buy other (hopefully better assets) but are now faced with operating highly leveraged bad assets.