I'll be interested in others' thoughts on this but how would Google know?
Three domains are probably better than one but I would consolidate all your material under one domain.
Why not publish the same site to each one? (three times the effort).
Then see which one is the most popular.
At some point, you'll probably have to use CPanel's Domain Redirect.
You could set up temporary Redirects for the less popular sites or jump in and make them permanent.
Do the same if the driver is financial but then just park or don't renew the other domains.
Acorn
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