Me and my lovely gf have live on Island of gods for 2 months. And now we can tell main info how to save your money and rich maximum from this amazing place.
Your future home.
Bali is a place that combine luxury hotel with enormous prices and cheap but beautifull homes on the same street. NEVER book your long-stay home at airbnb or booking. Try to find villa in facebook community or book home for 1-2 night and then bargain with property owner about monthly price. Our villa on booking costs ~900$ but we paid 280$ for months!!!
You have to know that island is big and if you want to see beautiful places or have some entertaiment you need to rent a bike or take a taxi. Bike costs 70-100$ monthly, taxi 20-30$ for one ride. We have tried taxi (Grab app) in the first few days but then we rent a bike.
Next time I'll tell you how to save your money at a touristic places, where you can find cheapest souvenirs and more interesting from Bali.