it depends on the value of the coins. Not all coins graded by PCGS or NGC go up in value when graded, low end Mint State coins are still cheap even in slabs. Dealers can't sell them for much, graded or not. Some people buy slabbed coins on eBay and pay way to much, in the end they will lose money when the sell. See a coin dealer for values on sending them in. You must belong to them or some dealer who does has to send them in for you. You will find the slab is not really greener on the other side in a lot of cases. See a coin dealer. Only rare circulated coins should be graded and to make sure they are real for common ones will have little value slabbed or not.