Or should someone get a couple of deals under their belt before incorporating?

I was an executive in corporate world (Dell), then decided to spend time with the family.

Can anyone shed some light on which state might be more advantageous to incorporate in vs the other?

Some companies have their own internal real estate divisions but then use 3rd party providers to place employees in corporate rentals.

If the value accurately incorporates the future income, take the payment you get and buy another similar property for a similar price and it should produce similar income.This is all driven from cap rates.

We are now going into baby steps #7 of FPU and would like to incorporate real estate into our wealth building.  

I've dealt with some lenders that will incorporate the rehab costs into the loan, but it has to be at an 80% after repair value. e.g. if you would need $90k for the property and rehab costs, the appraisal would need to come in at $112,500 after the repairs are complete.

The average length of stay in corporate housing is about 90 days.

is there anywhere on this site where it talks about how one should incorporate and if one should incorporate each property ?

Unless you want to wait until if/when the new ADU/DADU law passes (which would still require owner occupancy for 6 months), your best bet is likely to just incorporate the former MIL into the house as additional space for that single unit.