how to stay under the radar

I have a couple of sites doing pretty good with SEO, but obviously I can still milk the niche a but more. I am thinking of buying 6-7 exact match domains (same niche) and spin up a landing page selling the same service (websites will have a different layout).
I was doing some research and found out that buying multiple exact match domains and selling the same product is a form of spam & google is strictly against it.
what would be the safest way to do it?
I know that google can check any of these
registrar the domains were purchased with & when (if its the same registrar, and they were purchased in the same day, then it might flag it) I always use dynadot.
The place where the website is hosted (i will be using cloudflare pages)
The first time the site was indexed (if 6 sites with the same keyword in them started getting indexed the same week, that might be a red flag)
Google can go on the TOS pages and see that the same company is listed there
Maybe I am overthinking this (I am fairly new to SEO), can anyone with experience guide me on this one?

True they don't like multiple exact matches ranking much anymore but it's still possible.

You just have to make sure they seem to be ran by different people.

You listed most of the things that would give away there is the same person behind them.

Keep everything separate and you should be good.

If you are building 6 clones with same offer google will connect the dots anyway. Different registrar or hosting will not save thin duplicate sites. Safer play is one strong site and expand pages not doorway spam.

You’re probably overthinking it a bit. Owning multiple domains in the same niche isn’t automatically spam it becomes risky only when they’re clones of each other with the same content and intent.
If each site has unique content, branding, and real value for users, Google usually treats them as separate properties. Focus on quality and differentiation rather than trying to hide footprints.