RTGOAT's Longevity – This is a global mod that changes the mechanics of the game, making it more hardcore, complex and long-lasting.

Price Balance:

The profit from farming is significantly reduced. Crops with higher profits have higher seed prices. Selling prices increase when the player increases their skills. Goods cost more when they are out of season. Relationships with shop owners give the player price advantages. The value of cooked food is increased. Almost all goods have a random change in price (prices will fluctuate every day from a random 0-15% (in either a positive or negative direction), depending on what the item is). Seasonal influence will take into account crafted goods and what they are made of. Jam jelly will have the same seasonal influence as strawberries; the same goes for blueberries, etc.

Taxes:

At the end of each month (morning of the 28th) a simple menu will appear to notify the player of all the monthly expenses that will be incurred. The cost will be deducted from the player's bank. If the player has less money than the cost, they will go into debt which will be displayed as 0. Money will be added to the player but the balance may show 0 as the game does not allow for a negative balance. After the debt is recovered the display will be normal.

Taxes are calculated based on the size of the player's house, how many buildings are on the farm, how much capital the player has placed (on the farm and inside buildings).

Water:

Water bills are calculated based on the current size of the player's house, how many buildings are on the farm, and how many sprinklers are placed on the farm.

Electricity:

It is calculated based on the current size of the players, how many buildings are on the farm and how many engineering structures are on the farm and inside buildings.

There are also many other tweaks that will add realism and complexity to the game Stardew Valley. A great mod for hardcore fans of the game.