Is there an easy and careful way to stain a fence without getting the stain on the neighbors side of the fence?

My S-I-L just did her and my brothers backyard and did it by hand to avoid getting it all over the place. It took forever but she said it was the only way.

Stain it by hand. Watch out for getting an excessive amount of stain on the brush as it can lead to runs that could make it around to the other side of the fence.

Just another thought , who owns the fence? Are you co owners?

Our neighbors do and it they do not take care of anything in their yard. The fence has never been power washed or anything. It is actually leaning on our side.

I would check with your local laws before I touched that fence. If the fence is on your side of the property line, then you may actually own the fence. Check your local laws first. And for heaven's sake, if they do not take care of anything then you probably want the fence to be there and be TALL.