Start With Smaller Buildings
In Econia, if you don't feel comfortable with creating bigger buildings from the jump, then you can start off small (as with most things in life, am I right?). Starting off small allows you to get used to the nuances of the game, and understand how to maintain your city.
It's a bit confusing at first, but once you get used to keeping the smaller buildings afloat, then it won't seem as tough. At the end of the day, your goal is to keep customers, residents, and employees happy. If you do this, then you'll grow your wealth, and that's the name of the game.
You'll need to solve the problems that your buildings will have regularly. Getting these settled will open doors of opportunity for you to get your money. Take the baby steps and build a few small buildings first before expanding into adding more buildings and of different sizes.
Complete Daily Goals
One pretty easy and great way to grow your profits is by completing different goals that pop up regularly throughout your time playing. Usually, it's no more than three of them, and they can pay pretty handsomely, depending on the level of difficulty of the goal.
It could something such as building a coffee shop for example. Do this, and get rewarded. However, keep in mind that if a goal requires you to build something, then that means you'll have to spend some money to do so. However, as the old saying goes: "Sometimes you have to spend money to make money".
And don't worry because by completing all three goals, you'll get much more back than what you put into building something new. So this is something to definitely pay attention to because it can come in the clutch when you need that quick cash.
We touched on this a little bit already, but it is highly important to take care of problems that any of your buildings are having in Econia. Various things can occur, such as homelessness. This would mean that you might need to build another residence or apartment.
Other issues could be something like not having enough employees. What you can do to solve these issues is by forming Alliances which will help fill some of the holes that you might have. By clicking on a building and clicking on the problem(s), you'll see some things that can be purchased. Some will be free, while others will be 20 Econia bucks or so. This is part of the Alliances feature.
Problems might be solved for now, but they do pop up pretty regularly so be prepared. And as mentioned before, making a purchase of a new building can help solve the issues for other buildings, parks, etc as well so just keep that in mind.