Get pre approved so that when your rehab is ready appraisal gets done and you close without taking a ton of time. 

I asked an agent about typical bank appraisals for similar properties, and they suggested values between $100,000 to $120,000, which seems unrealistic to me.

The seller was a foreign landlord who was behind on a few years of taxes, and the property was in C5 condition at the time of initial appraisal.

I have a little concern as I offered a shorter financing contingency and appraisal contingency based on how fast it was stated they could close loans, but not entirely sure they can deliver yet.

Depending on the type of rental, you may be able to use 75% of the appraised rental income toward offsetting the monthly payment (reduces DTI).

If you buy a property with the intention to rehab and refinance (BRRRR) to pull your cash out, you'll need to wait 12 months to use the appraised value with a conventional loan.

Many lenders give better rates if the appraisers opinion of rents is 1.25%, 1.1% or 1% compared to the mortgage payment. 

Would like to add some value for “subject to improvement” appraisal to pull equity.  

Unfortunately, the appraiser valued the property at $159k.

An appraiser can testify as to the before and after values, assuming you can tell him what was done.