Guidelines suggest a fine of a week and a half’s net income (reduced by a third for a guilty plea) and a 12 month disqualification. You will also be ordered to pay about £80 costs and a £15 Victim Surcharge.
You should be offered the opportunity to take the Drink Drivers’ Rehabilitation course. The cost will be about £160 (varies area by area) and if you pay for it and successfully complete it your ban will be reduced by 25% (3 months).
If you intend to plead guilty you should not need representation.