hi... Sending it for certification with 0.5 Bitcoin is very risky, but yes, if they are certified, they have even more value, mainly because they will check the type of grading the coin has, whether it is low or high. That way, depending on the grade, it will have even more value. As long as the coin hasn't been manipulated too many times, it can have a very high rating. Regarding selling it on the forum, it is also risky, since you're dealing with a lot of money... 0.5 is a huge amount, and I believe it's a big risk to sell it here. I suggest removing the Bitcoin, storing it in a cold wallet, and selling the coin separately, certified or uncertified. If you plan to redeem it, I recommend cutting it properly in a circular shape to remove the private key and keeping the hologram intact so that the 0.5 coin retains even more value.