Phil I've always lived where there were snakes. Worse thing about a snake is finding it. Once it is located most people want to look at it but no one wants to be the one that finds it. Growing up we had lots of acreage and as kids kept anything we could in glass jars. Mama was canning once and didn't have enough canning jars, we had according to my dad 11 copperheads and seven rattlesnakes in addition to king rat snakes, ringnecks, lizards etc. My sister has had black snakes at her new house for years and they kill every one they see. Now the copperheads are back. She literally had one in her kitchen. They still don't want the black snakes.
Copperheads are most active at night but are often seen in the daytime. Pretty docile as are even rattlesnakes until disturbed. Only copperhead that was aggressive - really wasn't, he just wanted away from the wildfire we were fighting and he was between it and us. He lost. AMA reports that over 70% of reported snakebites were obtained either attempting to catch or kill the snake. Not exactly like they are after people.
Still, I couldn't abide them by the house so a hoe or shovel offers plenty of reach. Don't be fooled, a severed snake head can still bite hours after being detached.
Moth balls used to be made from camphor and napthalene but napthalene is very flammable. Most are now camphor and paradichlorobenzene. Just another chemical that really isn't healthy for people. Most sources cite moth balls not being an effective snake repellent, likely since there is no napthalene in them I imagine. Other say the mothballs keep most other pests (food source for the snake) away so the snakes don't come.
There are snake traps which have some effectiveness particularly with smaller snakes like copperheads but when dispatching the vermin there is another potential human intervention, aka bite potential. King rat and black snakes are pretty effective at reducing other snake populations but seeing a 5-6 foot black snake can be as unnerving to some people. Talk with a professional exterminator. They have some items that are not available to unlicensed homeowners. Independent labs have tested many of the commercial 'snake repellents' and not one has been found to be effective.
Keeping nesting spots cleared away and reducing their preferred habitat are about the best options. Usually means they will just move on in search of a better place to be - might be the back yard or a neighboring fence line - and they have a larger travel area than many realize...
Good luck with whatever you do!