As someone who was a huge collector back in the day and slowly is getting back into it, and whose son is really getting into the hobby...
Is it safe to suggest that the hobby is a whole lot different than the peak in the late 80s into the mid-90s? Back then it was about completing sets and collecting as many common cards, with the feeling of hitting the jackpot if you got a specialty card. Whereas these days it feels like (and certainly tell me if I'm wrong) it is the opposite -- common cards are ho-hum, and it's all about getting the 1 of X cards, autographed and/or jersey cards, specific players/rookies, etc. Not to mention the huge emphasis on having your cards graded to ensure their value and condition.
I'm of the mindset that quality is greater than quantity. Spend the money on the cards you are most interested in. I also speak as one, who perhaps is in the minority, who views card collecting as something for my lifelong keepsakes than merely investment opportunities.
It's not about any specific card. It is more geared towards gambling. It's not a good hobby for kids in that respect. Might as well just get him an account on whichever gambling site provides the best fan experience.
Meaning, there are cards that have more demand in the hobby, but at the end of the day the entire culture is built around people "breaking" boxes. People rarely keep what they break. They sell them to "pay for the box".
What you should do with your son is open a COMC account. Give the kid a budget. Let him buy the hits or inserts he finds interesting. Just don't leave your credit card linked to it, maybe pay for credit via cheque if they still allow that. Keep in mind, it will cost money to have the cards eventually shipped to him, but if you let him build up a collection and then do a shipment every few months it might be fun for him to anticipate that.
In terms of quality over quantity, the most revered cards in the hobby are The Cup RPAs, Future Watch Rookie Autos, and Young Guns Rookies.
Young Guns are very affordable for 90 percent of cards. Even big stars who have already peaked don't cost very much. For example, Erik Karlsson might be 30-40 dollars, Claude Giroux is 20 or so dollars. Those are both players who are possible HHOFs, MVP candidates, in contention for being the top player at their position for many years, etc. The thing about Young Guns is that most players peak when they first come out and demand for their cards is high or for rookies who aren't high picks they peak when they first break out. Outside of a small selection of choice players, or exceptions to the rule due to certain years being short printed, most cards from past generations of players don't have a high demand because the hobby is based around gambling and speculating and when a player is out of their prime that ends.
The Cup RPAs and Future Watch Autos are going to be a lot more expensive for any name players. When the sets are first released, you can usually get B or C type rookies for very cheap relative to the price of the product. Each pack of The Cup costs somewhere around 1500 CAD and has a few hits (autos and jerseys). So realistically, each RPA costs the person who originally opened the pack a few hundred dollars. A lot of the lesser names get sold off for 20-50. Sometimes less. The big names sell for four figures plus. If your son is interested in hockey or his favourite team to the point that having a highly limited and aesthetic Egor Sokolov RPA for $20 would excite him, then you could probably look to collecting The Cup.
If you go on COMC and you simply don't care about which set you buy, autographs are reasonably cheap for most players. It was better before the pandemic because there was an over abundance of supply that nobody wanted, so prices of all cards on COMC got driven down. People seem to have bought up that supply and it's partly reset things so now your average autograph is still a bit more expensive. We're talking $5-$10 instead of $1-$5. So they are still affordable. Some players sign more Upper Deck cards than others, but especially for players who have signed a lot over the last 5-10 years, you can get an autograph for maybe 95 percent of the league for $5-$10 a piece.
edit: If you don't know what COMC is, it's a giant warehouse for cards. Think Amazon FBA but just for cards. You can buy a card without having to immediately pay for shipping. You then "own" the card in your portfolio. You can either resell the card later on if you don't want it, or you can wait until you own enough cards to offset the cost of shipping. For example, it might cost $20 to have 1 card shipped to you, but $45 to have 100 cards shipped to you. 45 cents per card is cheaper than $20 a card. People generally sell certain cards for less on COMC for many reasons, but because it is all standardized it would be a good way for a kid to browse and purchase cards so long as you don't link a payment method on their account. (You can load a specific amount of credit.)
