9. Commercial Buildings

These are not like the factories, they produce items one at a time. But they produce items of great value. You can upgrade these buildings to make items faster. Before becoming an advanced player you'll need to concentrate on 5 of them:

1. Building supplies store

You can produce Nails, Planks, Bricks, Cement and Glue before level 16.

Max selling price of them are 80, 120, 190, 440 and 440 respectively. Production time is 5 mins, 30 mins, 20 mins, 50 mins, 1 hr respectively. People get in line to buy nails and planks so you can never sell enough of them. Other items are also sold but at a lower pace. Buy slots using simcash(don't confuse them with coins). In fact your only investment of simcash should be to increase the number of slots of commercial buildings and trade depot. 

2. Hardware store

Unlocks at level 4, costs 2500§

Makes Hammer(13 mins, 90§ each), Measuring tape(20 mins, 110§ each), Shovels(30 mins, 150§ each) etc. 

3. Farmer's market

Unlocks at level 8, costs 5000§

Makes Vegetables(20 mins, 160§ each). No need for more than 3-4 slots. 

4. Furniture store

Unlocks at level 10, costs 8000§

Makes Chairs(20 mins, 300§ each). No need for more than 3 slots.
5. Gardening supplies 
Unlocks at level 14, costs 13000§
Makes Grass(30 mins, 310§ each). No need for more than 3 slots.

Each item made in the commercial building needs raw material from factories or even materials from commercial buildings itself. Items are made one at a time so don't unnecessarily engage production slots by ordering materials that takes more time to make.

Increase your building supplies store and hardware store slots as much as your simcash allows(with some left in hand). Increase your slots at the trade depot as well so you can sell more items at once.