The cost of living in Hungary is relatively low, with groceries costing about the same or less than in other parts of Europe if bought in supermarkets and cheaper products available at local markets and some small shops. Many expatriates working for international companies or diplomatic missions live very comfortably in Hungary as their salaries are usually several times higher than those of local workers.

Typical costs include:

Litre of milk: HUF 210.00
Loaf of plain bread: HUF 220.00
Small bottle of local beer: HUF 180.00
Litre of bottled water: HUF 110.00
Bottle of simple, basic, everyday table wine: HUF 490.00
Litre of petrol / gasoline (octane 95): HUF 340.00
Restaurant meal, not fancy: between HUF 900 and HUF 2,800.00   

The currency used in this section is the Hungarian Forint (HUF or Ft) which is the official currency in Hungary. The Euro has been the standard currency of most of the countries of the European Community since January 2002, and it is expected that Hungary will start to switch to the Euro in 2010. Consult the currency converter for the current rate in your currency:
Universal Currency Converter - http://www.xe.com/ucc/

Comparison: Budapest, the capital city of Hungary is only the 24th most expensive city in Europe, but is the costliest city of the former 'soviet block' countries that joined the EU in 2004. “Many cities in the new EU accession countries have risen sharply in the rankings this year, as they make strides to bring their economic infrastructure up to EU standards. Central and Eastern Europe are becoming increasingly attractive for investment by multinationals”.
Source: EIU surveys, Most expensive cities -  http://www.citymayors.com/economics/expensive_cities_eiu.html 

Lowest incomes in the country: In East Hungary, an average of 40 working hours per week, blue-collar workers earn an average of EUR 370, while white-collar workers make an average of EUR 700 per month (both are gross salaries).  In the same region, electricity costs EUR 4-5/kWh/month, industrial water costs EUR 1/m3, drinking water costs EUR 0.7/m3, sewage costs EUR 2-3/m3, gas costs EUR 5-6/MJ/h. If you do green-field investment, you will need to cover the one-time utility development fee as well, based on the required capacity.
Source: http://www.filolog.com/costofliving.html