Peugeot 307 sw - 03 - blowers working intermittently - salvan3003

hi, i was wondering if anyone can help me. My blowers on my car just cut out one day. i had an auto electrician come out and he changed something on it (not sure what it was). about 3 months later they stopped again. once again this part was changed and all was okay for a couple of months. then yes you've guessed it it stopped again. this time i couldn't afford to get it fixed and as it was summer i was managing fine. thenm of course winter came and it caused a few problems and then when the snow came it was undrivable - i know i should have got it fixed but i honestly could not afford to (i had just lost my job and was losing the house too - Now i have a job but sadly still lost the house) anyway, after the snow had all gone i was driving my car to pick the kids up and magically the blowers started working!!!!!! it has been fantastic for about 6 weeks, having heat but alas that all ended on Saturday morning when we set off in the car and noticed the blowers were not working again!!!! Yet 2 mins later they started again. but yesterday they stopped again and still do not work. i would have thought that with the blowerrs coming on on saturday while driving that it is some kind of loose connection. but where do i start. is it something simple or should i expect a huge bill if i take it to the garage. any suggestions would be gratefully appreciated.