How do I force Apple Podcasts to download only the most recent episodes?

I've tried removing iTunes and redownloading a new app installation. It seems that since my computer is authorized that even when I totally remove a pocast subscription and try to renew it as a new podcast, I get a hundred or so podcast download. How can I force the configuration to obtain only 3 or 5 based on the subscription settings?

[Re-Titled by Moderator]