60s Scottish Laird rents out his castle

I read this paperback in the late 60s or early 70s. Main character is a Scottish Laird who owns a castle and estate which he rents out as a B&B to make ends meet. He is either widowed or divorced but has a daughter and Mini auto, both of which which he loves dearly. He rents to an Italian Count who drinks Negroni cocktails and is trying to avoid criminals (mafia?) who seek to do him harm. Turns into a pitched battle defending the castle with both modern and antique weaponry. Book is written in a breezy style. No great drama but a pleasant and somewhat exciting read when I was young.

At the time I found one other book by the author about a British man visiting Canada. Don't recall much more about that one except the MCs in both books are interested in forestry and actively work to create healthy/attractive woodland using chain saws to clear out underbrush, space out trees, etc.

Thanks for any help you can give.