Training: are you having fun? If yes then continue and enjoy it, if no then stop. Try different types and clubs. Go to Cambidge Flying Group for a trial lesson. You'll get the best part of an hour for a ton in a Tiger Moth. Even if you don't qualify you will have a ball. My mate had ten types in his log book and forty ours before he soloed. He still hasn't qualified for medical reasons but he gets about ten hours a year dual.
Cost: Slingsby, find a gliding club with one. It will cost you a couple of hundred a year membership but flying will cost you about sixty per hour. This will usually include instruction.