Hi, I have been collecting original comic art for about 15 years. I am not wealthy. I don't have any high end art. But I have a very nice collection of pages, commissions, and underground stuff that I have collected over there years. These are somethings to consider when you start out collecting.
Start slow. Buy what you like. Be prepared to wait long periods of time for pieces/characters you collect to become available. Don't spend tons of money all at once because you can never buy everything. Don't be afraid to negotiate politely. Don't be afraid to walk away from a piece if you think the price is unreasonable. And the most important thing of all: Store your art correctly. Repeat, store ones art correctly.
Just remember, collecting art for ones enjoyment is different from buying art as an investment. I know they both go hand and hand. But compare it to being a sports fan and someone who bets on sports. Sport fans love their teams to win, gamblers don't care who wins, they just want to beat the spread. Happy collecting.