Weekly expenses! Now that is a "how long is a piece of string?" question! ;-)
You are required to agree to employ Indonesian staff when you get a stay permit, so you should factor this into the living expenses equation. It is helpful at least to have a pembantu (helper) to look after the day-to-day cleaning of the house. Most Bali places are open-plan, so they get dusty quickly with daily cleaning. Many people also employ a gardener (1-2 times per week for 2-3 hrs)and if you have a pool, a pool guy 2-3 times a week.
A pembantu will cost 1 - 1.2 million per month. Be prepared for many days off for ceremonies if she is a Balinese, or various Muslim holidays including a paid 2 week Idul Fitri holiday if she is from Java. Many employment agreements incorporate a 13 for 12 arrangement - i.e. at the end of 12 months, you pay an extra month's 'bonus'.
A pool guy will cost about 350,000 a month fro a small pool; more if your pool is big. Some pool guys include the cost of chemicals, some don't.
Gardener costs vary, depending on garden size, but rates are similar to pool guys.
You will probably need to pay a local to take away your garbage. This will be between 50,000 and 100,000 per month.
Water costs vary widely, depending on whether the villa water supply is from a well (in which case the cost is usually included in the villa lease)or from the water supply authorities. If on metered water, expect to pay 80,000 to 150,000 per month, but this depends on which of the local banjars (villages) are responsible for your water supply.
Electricity can be very expensive in Bali. I am lucky - my current villa has a pre-paid meter, so I buy pulsa (credits) and code the meter when it runs low. For me, living modestly, it costs about 350,000 per month - double or even triple that if I have guests that leave lights on and run the airconditioners in their rooms all the time. My previous villa had a 'normal' meter, and that one cost me about 2.5 million per month even with no-one else there.
Faster wifi internet (there really is no 'fast' internet in Bali) will cost about 600,000-900,000 per month plus installation of 2 million or so. This is the type with a roof-mounted antenna feeding a modem and wifi router. Alternatively, internet via the phone line is about 700,000-800,000 per month. If there is no landline at your chosen villa, be prepared to wait for up to 10 months for a line to become available, and even then you might be 'encouraged' to pay a large bribe to secure this.
Cable or satellite TV is another 600,000 - 800,000 per month if you must have international TV feeds.
Alcohol: Beer is cheap, but imported alcohol has suffered from the duty imposts imposed by the anti-alcohol Islamist lobby in Jakarta. Duty is 350%, plus taxes, so a typical bottle of Australian wine that costs $8 in Aus will set you back the equivalent of $35-50 here. Spirits are the same - a Johnny Walker Red Label costs close to $90 here. Local wines are ... well, basically undrinkable.
Food: You will get away with 20-30,000 for a meal in a cheap warung, 60,000 - 80,000 at a reasonable restaurant, and 200,000+ at the fancy high-end places where being seen is more important than the food. Drinks are extra. Many restaurants will also charge 10% service charge + 21% government tax on top of your bill, so check the menu before you choose.
Finally, you may be expected to donate to the local banjar from time to time as a goodwill gesture. This can become very important should you ever require the assistance of the local village heads in cases of theft, noisy neighbours, staff problems etc.
Hope that gives you something to plug into your budgetary spreadsheet ;-)
Cheers
Vyt
p.s. Vyt is a Lithuanian name - that is my original heritage.