Now valued $90k and $75k and cash flowing.Need to pull cash out to fund medical care for sister.Have been offered a 60%LTV loan at 7 1/2% adjustable rate over a 20 year period.

In addition, when you purchase a house in Washetenaw County the taxes will be adjusted the following year. 

I would start with finding the local rate paid to management companies for their services, adjust up or down for the service level your partner intends to provide and figure you will be responsible to pay for 50% of the total. 

I might do a price adjust based on tenant quality, but that's it.The operating principle is when a deal closes its closed.

I've used other companies in the past but he provides me with the product that meets my needs and lets me adjust my policies as needed to make sure it's the coverage I need not what the insurance company is selling.

Or should I abandon the hope of getting a loan any time soon and adjust my strategy to only involve flipping for a while? 

It's based on the net sale price minus your adjusted basis which is the purchase price minus depreciation and plus capital improvements. 

In 2019 I believe for a single person max income limit was 139K..With my job and all the investments I am afraid what if I am making more than 139K in MAGI (Modified Adjusted Gross Income)?

After this, you subtract out certain adjustments to your total income (many people won't have adjustments here).

The letter is good, but I would adjust a couple of things.