Ok so I went last month for a few weeks to Thailand and I saved a lot of money by using my own brain. But I want to share it with you! I stayed in the most expensive hotels in Bangkok for 50% off

(Anantara Sathorn, 38th floor, 120 sqm room, free drinks and food for just 45$)
There are 2 methods.
1. Book in advance on the site of a large Hotel company. Most times you can save up to 60%! You need to book at least 3 months in advance. And if they don't offer discount just call them or email them if there is discount available when you stay longer. My stay in the Anantara Bangkok hotel was normally 180$/night but I got it for 45$/night
2. Look on Booking.com for rooms. Be sure not to book in advance with this method!!!! This is absolutely last minute booking but it works 9/10 times. In Bali it should be quite the same as Thailand. I stayed in Villa's for the price of bungalows. Now here is the trick. Room owners who advertise on Booking.com need to pay at least 15% fee to Booking.com. If they want to become secret deal or whatever they pay up to 30% fee. I hope you get it by now... find a villa/bungalow from a small owner or company (Hilton or similar won't work for sure - haven't tested it but ok). In Thailand the dude had like 5 villa's but 1 was still available for the next 3 days, secret deal, 3rd listed on the page, etc. he was at least paying 20% fee over $600 total (atm I was with a few friends, but for smaller rooms this will work too). That's 0,2x600=120$. So I looked up the phone number from the company with the villas. Called them, I said we book the room for 520$. (He earned 40$ more then when I would book this via booking.com and I was saving 80$). He accepted immediately.
Some hotel owners won't accept at once but they will call you back with offers. If they are really desperate just say no and they will call again with a better offer.
Sorry for the long post but don't want to re-read and delete useless stuff