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What I have implemented is is monthly withdrawal from CEX to my private wallet even though I'm using weekly DCA combined with buying the dip... all my purchases are withdrawn to my private wallet monthly. I know this is still risky but the risk is highly minimised as not all my Bitcoin will be exposed to such risk.
Not all investors understand how when they store their assets in CEX they can be exposed to the risk that their assets could be lost if the CEX goes bankrupt. Storing bitcoin in a non-custodial wallet is the safest and most secure thing that investors can do, because their assets are in their hands and they can manage it whenever they want without having to worry that the assets will be taken by other parties. And for fees, the way you do it can be done by beginners to minimize the fees they need to pay to move their bitcoins from CEX.
Maybe the extra security that investors need to do is they need to secure their devices and separate their daily devices and devices for their bitcoin wallets. Or more securely using a hardware wallet, but that might be more expensive for beginners. But the most important thing is that investors need to understand the security of their devices, so that their wallets can be kept safe.
If they don't want to worry much about the safety of their device and that of the wallet at the same time they can delete the wallet from their phone, provided they have the wallet phrase well written down and safely stored where no body can access it. Provided such investor don't have need for the wallet on daily basis there is no need keeping the wallet on the device, as it is very risky to have your wallet that you are storing your long term investment on a device that you are always moving around with. Nobody knows what might happen the next minutes, one can be a victim of kidnappers or armed robbery and if they happen to see a bitcoin wallet in your phone, they will force the person to open it and if they see your bitcoin investment in it, they will withdraw everything from your wallet. But if the wallet is not stored in your phone, there is no way they will know that you own bitcoin.