As a post card collector, I would be thrilled to inherit
a post card collection from a loved one and realize that he enjoyed looking at them, studying them if you will for many years. That's how I started my 6,000 cards collection. That is a priceless thought! So, congratulations in that regard, not so much the monetary value.
The cards you show are from the classic period of post cards before 1920. I think the best of the lot is the 1909 pictorial of the huge celebration in New York jointly commemorating the 300th anniversary of Henry Hudson discovering the river now bearing his name, and the 100th anniversary of Fulton's invention of the paddle wheel steam boat. It would be 'nice' if that card were mailed with the Hudson-Fulton 2 cent commemorative stamp affixed. If I wanted to buy that card I would expect to find it available $5 to $8.
Betsey Ross sewing the (not really) Colonial flag is a common theme, has a pronounced fold damaging the bottom, and a bumped upper right corner. But the colors appear bright. I would cut a small triangle of thin white stock and paste it on the back to stabilize the corner, but don't damage the stamp pr message. With the repair, I would be glad to trade the seller a coffee and a doughnut for it and leave him with a smile.
The President McKinley 1 cent with the Presidential seal is a moorning issue following his assassination in Buffalo. The distinctive heavy black writing of the address adds to its collectibility. The card is readily available. Maybe $3 to $5.
Lord knows the interesting cards and stamps you may have there. If I saw such a hoard for sale in a local craig's for $100 I would want to see them.