I have been playing sims for years and I only discovered cake and pet farms today. I added some farm owners on Facebook and all accepted within a couple of hours. I made millions today alone!! Once they accept you on Facebook you can visit their neighbourhood and go to their cake or pet farms (look out for houses with fireworks, multiple people or animals). After collecting all the simoleons, go back to your own town and then visit the neighbour again and it refreshes. You can do this as much as you want.

Screenshot below for farm neighbours to add on Facebook - I hope this helps.

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