I second this... I spent so much money on the mine and smelter and i hardly use it now, i have no need for the bars until i get the jewellery maker anyway and for the amount of time they take, they do not sell for much.
Try to make sure you put stuff on to queue before you leave the game ie. for bed or dinner...whatever, even if it is something you are not going to need, sell it.
I find cheesecakes sell really well, and i have a stock of cheese and cookies and so i fill my queue up (4 at the mo) and by the time i come home from work the following day i will have made 2,000 coins from me not being online.
Being level 35, i've only just gained access to the jam maker and bought it as i had saved up coins beforehand. I find it doesnt do much for me yet as i can only do apple jam and it take 6 hours to do and doesn't sell for that much, but i like to have it to help out others who may need some for boats and truck orders that they are doing. Xx
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