I figured out two new coin method you can use ..
First coin method : when you level up and have a skill point , instead of adding the skill point keep spamming the refresh button as every time you click it you’ll get 10 coins which can stack up a lot depending on how much you click it.
Second coin method : Go into the store, go to the transport section , and once you have at least 50 coins from the first coin trick buy the gas in the bottom right corner over and over again til you get 200 coins .. than once you have the 200 coins you buy the most expensive gas which is 200 and keep on buying the gas over and over again til you have as many coins as you want ! It’s unlimited and you will only gain coins from this not lose them !
This is for the people that didn’t know you can do this but anyways hope I helped out 🙂