Murders and Cupcakes. A Dangerous Game of Grandma (set of 2 books)

Murders and Cupcakes. Detective Agency "Charity Store" (#1)
Fiona, Sue, and Daisy – three charming retired ladies working in a small charity shop. One day, the peaceful rhythm of their lives with coffee Tuesdays and walks through the lovely streets of Southbourne is disrupted by the brutal murder of their beloved customer, Sarah Brown.
Refusing to accept such injustice, they decide to take the investigation into their own hands. Especially since a new body appears, and the police are completely stuck. Armed with their knowledge of detective stories and, of course, tea with excellent cupcakes, the three sweet old ladies embark on active measures. Thus, the Detective Agency "Charity Store" is born.

A Dangerous Game of Grandma. A Guide to Solving Your Own Murder
Good old England, 1965. A fairground fortune teller predicts a terrifying future for sixteen-year-old Frances Adams: one day the girl will be killed… Since then, she has devoted her entire life to investigating a murder that has not yet occurred. No one took Frances's fears seriously until, sixty years later, her body is found in the library.
Our days. Annie Adams is invited to Gravesdown Hall - the vast country estate of her eccentric great-aunt Frances. But when the girl arrives in the quirky village of Castle Knoll, the old lady is already dead. And under the terms of the will, all her vast fortune, as well as the estate, will go to whoever solves this murder. The investigation is complicated by Frances's habit of gathering compromising materials on everyone. It seems that every sweet and quirky local resident had a motive to kill her.
Together with another heir, Annie finds herself drawn into an extremely dangerous game. And the closer the solution gets, the more fears arise that instead of Gravesdown Hall, she will inherit the sad fate of her grandmother…