I have a couple of questions.
1. Is the edge you are speaking of in direct sunlight?
2. Is there a tree over the house in this area?
3. When you scrap and paint it are you taking it all the way down to the wood?
4. Are you then putting a coat of primer and a coat of good latex based paint? You get what you pay for when it comes to paint. I personally like Home Depot, Benjamin Moore and Sherwin Williams paints.
5. Do you have gutters that are cloged with leaves which allows water to stand?
As far as maintenance free I can't think of anything other than having a company come and put an aluminum or plastic siding over that edge. To do that at this point though would entail pulling the roof up at the edge in order to install everything.
www.thisoldhouse.com is a good reference for home repair and maintenance as well ashttp:// www.DIYnetwork.com
Keller Williams Realty