Deductions & credits

Childhood home in name of family trust with mom & step-dad as trustees.  Mom dies and house stays in trust with step-dad as everything passes to him & he decides to gift house to my sister and I since mom passed.  Mom bought house in 1970 for $10,000 (with our biological father who then divorced and mom awarded house) and tons of repairs over the years and then marries step-dad in 1994 and then transfers house out of her name & into their trust in 2004 where they are joint trustees.  FMV when mom passed in 2020 around $195,000.  When step-dad gifts to us in 2021, FMV around $225,000.  Unsure of anY gift taxes paid by him to IRS (btw- house has been used as a rental for 25 yrs and is currently rented if that matters).  If we sell, how do we calculate (gains) for taxation?  Also, are there options to reduce taxation if we do an 1039 exchange with either of our sale proceeds for myself or my sister?  Or could one of us buy-out the other to reduce taxation?  Looking 4 options but most likely sell.  Thank You!