A mortgage payment is a combination of the amount, terms, and rate. 

Yeah, so we try to identify the most optimal combination of high cash flow and high appreciation potential.  

True, if you are an investor that likes to work in the shadows since you have things to hide, or one that simply does not care about doing things right or one that is just a straight up slum-lord or any combination of the three.If you change that mindset and engage them (within reason without opening up a can of worms).....for example find out who the Code Enforcement Officer is in the area you own properties or intend to purchase properties.

I show houses for a living to people as a Realtor and one person says I hate modern, the other says the love modern.  

Are you investing for cash flow, appreciation, or a combination of the two?

It's far from a modern door.

I have yet to find a source that allows for a higher combined LTV with the seller carrying a 2nd where the rate/terms actually make sense to take that on.

I didn't realize you had to combine a 504 loan with a standard loan. 

You could structure each sale as a separate 1031 Exchange or you could structure them as one combined 1031 Exchange depending on the timing between the sale transactions. 

I am active in distressed REI and I also bike, but can't say that I have combined the two!