Yep, they're real

Another implication of the passages of Scripture we’ve examined is that the notion of demonic strongholds is biblical. We aren’t given a full description of demonic zones or turf boundaries, or even a spiritual pecking order for the dark side. We are told, however, that the unseen powers see earth as their domain. We’re told those powers resist God’s kingdom and don’t want people to become part of God’s plan to spread his good rule everywhere. That means we should expect resistance we can’t explain with logic or empirical evidence and we can’t defeat it on our own. God has given us his Spirit and unseen agents of his own to help us further his mission (1 Cor 3:16; 6:19; Heb 1:13; 1 John 4:4).— Supernatural: What the Bible Teaches about the Unseen World—And Why It Matters, page 133

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Mind you, this is written by a non-Charismatic! Further, he is correct—on both counts: demonic strongholds are a biblical concept. And, most important to remember for those who want to lay out a roadmap, we aren't given the details. Nor should we spend a great deal of time trying to develop a roadmap. It's a distraction from the task of living a godly life and shining in the corner of the world where God placed you.

3 By his divine power the Lord has given us everything we need for life and godliness through the knowledge of the one who called us by his own honor and glory. 4 Through his honor and glory he has given us his precious and wonderful promises, that you may share the divine nature and escape from the world’s immorality that sinful craving produces. (2 Pet 1:3–4 CEB)

What more do we need?
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