With a MTM, it gives me so much more flexibility in potentially giving a 30-Day Notice to adjust rents, add/subtract lease terms, and/or weed out problem tenants.

HELOC is just a credit line, So you can buy/rehab and refinance with a regular loan in order to pay back your HELOC if you want or pay back the HELOC with time.Depending on the type (1% Payback or Interest Only Payback) if you borrow 80k, your monthly payments would be $800 - if you were renting for say $1000+ and covered all expenses, then you could just pay back your HELOC and if rates adjusted, your payments is still 1% payback - you would just have more interest added on for the life of the loan.I have a HELOC and opened it up to be able to fund my rehabs or have extra $ to close on a deal.

@Marian Smith In your Wells Fargo analogy you would need to treat this as a Wells REO in which they financed the new buyer yet failed to adjust taxes to the settlement date. 

I called up the insurance company and they sent out their adjuster and he's giving me an 80k estimate I don't exactly trust.

The part of adjusting for inflation?

Suppose you have a subject property with a 105,000 sq. ft. lot and existing improvements for which you estimate the reproduction cost new to be $2,500,000, physical deterioration to be $400,000, functional obsolescence to be $50,000, and external obsolescence to be $50,000.If you have information on a comparable lot of 110,000 sq. ft. which recently sold for $250,000 and the only adjustment is $1.75 per sq. ft. for the difference in lot size, what is the indicated total value for the subject property.

I've searched around and found some great insight on SELLER FINANCING, but I'd like to see if I can dig a bit deeper...My hypothetic deal: Seller is asking $250K for his turnkey 6plex.Gross income is $36,600yrI've yet to get an answer as to why the seller is open to selling, I replied to a for rent craigslist ad just asking if the owner might be open to selling the building?

And there's always things you can do like rent abatement or adjustments to purchase price to accommodate your need to find a good replacement property.   

You should also understand the concept of risk-adjusted returns (which is why coastal markets, often beat non-coastal markets). 

It may be several years, but eventually the market will make an adjustment, so be ready to pounce when others are running the opposite way.