Mice under the hood on the daily driver
 

It's kept outside, noticed some dropping around. no damage to wires etc. They aren't nesting just hanging on the warm engine cover.

Bought some spray from Amazon, anyone have any other thoughts?

You need a cat.

Yes, this item(s).

Tomcat Store - Refillable Station

Put out several, if you have mice you may have rats as well.

If they are there, they are doing damage. Means they have already moved in. Bar bait is the best way. Put water out for them close to bar bait......makes them thirsty and draws them away from car before it kills them.....no dead smell in csr.

Well, if daily driven, they aren't moving in just yet. Just sleeping on warm engine like you said. So its not that bad, yet.

But it needs to stop before it does. Barring cat suggestion, the poison is not humane, but will work. As said, makes them very thirsty, they leave to seek water, die elsewhere...where some larger animal will eat them and maybe die too. Not ideal.

Traps are a another solution.

Deterent may be the best solution, since it may not be possible to eradicate all the mice living outside in that area.

Mouthballs, Cayenne pepper, commercial deterent products, etc.

Peppermint oil on cotton balls here and there.

Why would somebody think that if a car is daily driven mice wouldn't move in? See it all the time. It is a real problem in the area I live in. There is no time stamp when you smell mouse piss in car compared to when they move in. And they carry several diseases. Eat wires and love carpet and its insulation/sound deadner. They like McDonald's drive thru as much as the next guy.

In the northern climes, like northern New England, many believe that it is best to wait until late fall to put your cars to bed in the barn because by then the mice have already found their winter homes and they are less likely to be interested in your car assuming of course you don't have McDonald's tid bits all over the floor! Not sure if this applies further south.

Because they won't find an engine bay a suitable environment when the car is running and driving around.