welcome to the family!
some things i've learned from playing a while:
Buy at least 3 of each item during new releases (more if they're super cute, or a 1-day sale!) so you can keep one for yourself, and sell more when the value goes up! There are new releases every week sold in a different store under specials. Using this method has helped me a ton! After a few months the value usually rises because new or returning players missed those items. After a few years, too, the value may raise even more! It's an investment that pays off.
Find players to play friendly games with like Haunted Mansion or Pirates! Friendly pirate battles will get you more credits and is a quicker game
Sell all of the extra clothes in your inventory that you won't wear. Sell the normal items (like the default clothes and furniture) right out of the inventory tab. Those few credits will add up a bit to start you off.
Once you've gotten a bit of credits, auctions are a great place to get awesome items for a cheaper price!
Just like in OG VMK, players often host games like DHTF, Cute or Boot, Falling Chairs, and many others! Always give them a try, because there's almost always a credit prize.
Also - find me in the game! I always give newbies a few uncommon items to start them off!
I hope you have a ton of fun!