That said, some attorneys advise that a comparative market analysis or a broker's price opinion is sufficient.

Compile sufficient info to prepare offer.

Courts have already held that a claim of "entrapment" is not a sufficient defense.

.- no title seasoning on cash out refinances unlike FHA which has 12 months of title seasoning after purchase before you can use market value value or conventional which requires 6 months after acquisition (this applies to CO refinances where you used financing initially to purchase not DFE or delayed financing exception which is an all cash purchase and there is no lien/deed recorded on the property at the time of close), This becomes very handy for  creative RE entrepreneur once you learn how to force equity through adding value to properties you can use VA's no title seasoning advantage to increase the speed at which you move from deal to deal quicker than Conv/FHA- no self sufficiency rule when owner occupying 3-4 unit properties which FHA has (a rule that makes buying 3-4 unit FHA properties in high cost areas nearly impossible) so this a huge plus- use of rental income or other peoples income (OPI) to help you qualify on your 2-4 unit VA purchase (FHA and Conv does allow this too)There's a lot more you can do to optimize your mortgage planning from an investors perspective.With the introduction of the 2018 Tax Cuts, you can structure your taxes strategically to not only greatly reduce the tax impact but also remain bankable to most money sources.

One good startegy is to BRRR (or better BRRARR) a property - the financial sustainability of the approach over the life cycle of the investment is usually not pointed out sufficiently - a fully improved property will yield higher rent and require little money for repairs and maintennace in the first 10-20 years.

Say it converts on 10/1, is it sufficient to use redfin and zillow as an estimate? 

Is that sufficient?

So A might be sufficient.

If so, do you have a sufficient amount of equity available?

Another option is to just offer here a token amount of money for a quit claim to her half.