3 phase leccy and other utilities questions

[voicey]

I'm very close to completing the purchase of my first commercial unit (I've never rented one either) and thoughts are turning to getting the business moving as quickly as possible. The unit has a three phase supply yet I have no idea what this means practically. All of my equipment is single phase and anything I will buy in the future could be supplied in single or three phase. I would be grateful if those with more experience could enlighten me on a few points...

Are there two meters (one for each supply)?

Is three phase more expensive than single phase?

Can I elect just to use single phase or do I have to pay for both?

Any tips when dealing with the electricity company when I get the keys?

Can I choose a different (cheaper) supplier like I can with a domestic supply?



Additionally, I'm going to need a single phone line and broadband. Any suggestions on a company to supply these are am I stuck with BT? The unit already has incoming supplies for both so I don't need to have a line physically installed.

Any tips on dealing with water companies? Water will only be used for washing hands/flushing the toilet and washing the odd car.

Thanks in advance....