The current hourly rate with Jay at Plaistows is £80. He will lend you a flying suit when you train with him (and will expect you to buy one from him eventually). You'll need to buy your own balaclava and bar mitts (about £24) - essential for keeping warm between now and next May!
Learning on a weightshift is a realistic proposition during the winter because the school aircraft is kept fully rigged and you won't be out in the cold for much longer than an hour at a time. The tricky bit is rigging and de-rigging an aircraft in the cold during winter!
Jay lets his students fly solo in his school aircraft provided you pay a contribution to hull insurance (fair enough). And you'll need to have your own third party liability cover before you fly solo (about £80 per annum).
Also budget for 5 lots of £15 for exams, £28 for charts, plus ruler, protractor, chart pens, etc.
Also join BMAA right away - they are very helpful and their magazine "Microlight Flying" is the best source of information on the sport.
Good luck
Springers