I think you are aiming a little high, myself, but I would get the word of a few others before considering it written in stone.

Reverse the numbers a bit, say $1.00/month with 2,000 sites, and add more monthly.

But it all depends on what niches you choose, the SEO you put in to them, the sites layout, and a few other factors. Heck, you could hit on 20 hot niches and do it, but remember the hot niches change, so you have to keep up with the times.

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