Well it depends what you mean by cheap-ish.
I notice that a guide with Arc Adventures would cost 315 euro for a group of between 3 and 8 people for a full day. If there are 8 of you then this is significantly less than the 66 euro a day for a group lesson.
Bearing in mind that you would certainly not be working every day of the week - or all season - then if I were a guide I would regard it as a give away.
Which reminds me that I must employ a guide for a few days this Christmas.