Trying to go at it solo will only get you so far - and it's gonna be way harder to grow something substantial. 

At a purchase price of 675k and an ARV of 975k the difference in property taxes would be substantial and my understanding is that a reassessment os not triggered if we purchase owner occupied and just refinance.Has anyone done this and can share their experience?

That means that I can no longer do FHA because my debt to income ratio is too high so we have to switch to a 15% down Conventional Loan ($54,150 down payment) which is substantially more than we were thinking we would have to pay. 

Answer: The home from which the property owner wants to transfer the base year value must have been the owner's primary place of residence as of one of the following: (1) the date of the sale of the original primary residence, (2) the date of disaster that resulted in the substantial damage or destruction of the original primary residence, or (3) within two years of the purchase of the replacement primary residence.

Hi - I am filling out a Substantial Rehabilitation application for a couple of units in a rent-controlled building. 

If it is in an A+ location that you feel is going to generate substantial appreciation, I'd want to weigh that in my decision making, so I'd look at the total ROI on my investment, assuming what you think the property may be worth in the future. 

I'm already dealing with the substantially higher interest rates on the mortgage this year as opposed to last year.

If the cash flow substantially outweighs the extra interest you are paying it might be worth it.

Signed the contract. 4K upfront and then there was going to 25K upon substantial completion and another 4k or so at the end.

I’m assuming the costs of fully refinancing an in process flip are substantial with duplicative title fees, etc.