Credit scores are a reflection of someone's ability to learning and understanding the rules of the game and haveing the discipline to play by them.If you already have good credit, already pay everything on time (autopay), then increaseing your limits will probably help you the most, because it gets your utilization down, ideally under 10%.Higher hanging fruits are average credit and account age (just have to wait for that I guess) and inquiries, which are sometimes unavoidable as real estate investors.  

I just keep plowing money into the mortgage  my goal is not to have it hang around long term so I would avoid the recast idea .

Hang in there, and good luck!

Quote from @Miguel Del Mazo: “Don’t put all your eggs in one basket” is all wrong.

But hanging onto to some of those rates isn't always a bad idea. 

Let one Tennant hanging with defective outlets in the kitchen for 2 weeks when the townhouse was it was under warranty.

Generally, I would be tree trimming once a year to cut back any branches hanging over the houses because of potential damage, but also because of insect transfer.

I am prioritizing cash flow and number of units to try to mitigate some risk of all the eggs in one basket.  

I would prefer not to keep all my eggs in one basket.

You are going to most likely have a stranger hang on to several hundred thousand of your dollars.