In order to stay on the first page you'd have to stop everyone else from posting new listings or updating and renewing old ones. It's a dynamic, not static thing.
What you are asking is "How can I guarantee I will always win a race?"
The answer is "Be the only one running."
And it's not necessary to be on the first page for something to sell. I have one item that's on the first page all the time, yet I haven't sold that items in 3 or 4 months. I have other items that are never in the first 20 pages and sell regularly.
You could churn it and new items often and they'll get up there, but they'll quickly sink.
