I don't think i'm using regions to their full potential, i just keep trying to play in the one section i pick and cram everything in.
Anyone know if i can have a mining/drilling city which can just be left making money while i'm building the actual city that i want??? then abandon it once i'm built up/
Mining/Drilling town isn't viable as you will run out of resources fast, what I would recommend is that you start out mixed and the move into metal production focusing on Alloy.
Then as you finish extracting Coal and Ore just change your trading buildings to import those resources. Both cost about $13k for a product that gives you $46k back.
Once you have those set move onto adding processor factories and then sell those, its at this stage you need to hold a large stock of the processors so that you can do a mass sell of them to level up your HQ to open up the electronics factory.
Either sit happy or do another build up and sell to get the final level on your HQ for all building options.
Once you have commodities up and running you can run a massive deficient on your budget and still make 1-2 Million a day.
Last calculation for a month I was at 100 Million, so far I've chucked 20 million at wiping an old city and rebuilding it from scratch and building a oil coast tile.
Also only one tile is active at any one time on your account, so no leaving the other tile to accumulate cash, also the game has an auto kick feature. I think its 20 minutes and then the server boots you, also you cant alt tab out of it and keep it running.
If you want to build a wonder always make Processors, TV's or Computers as the Fuel is so cheap to buy in that its pointless producing it.