Best way to look up historical value - cost basis adjustment

[Donnie N.]

Any suggestion on the best way to look up historical comp value of a home?

Background…

1) fahter-in-law sold a home recently. Need to pay the capital gains tax.

2) Trying to look up the historical value of the home as the deed was transferred when wife passed back in 2010. Basically, looking to see what the adjusted cost basis should be for this property.

Any recommendations? This property is in Montgomery County / Silver Springs area.