Alarm goes off and indicators randomly come on!!

I am really losing it with the old Peugeot Garage.

x reg 206 GTi

I drove through a puddle about 6 months ago and evr since then Ive got
problems. When it rains the alarm goes off randonmly so ive resigned
myself to the fact of using the isolator switch inside to just set half
the alarm. It went into Peugeot and they fiddled with the bonnet switch
and said it was ok. Charged me, and by the tme i walked over to the car
park the light inside showed that it had been activated.

Secondly the left indicator has started going of by itself at random
times. Usually 1st thing in the morning. As it didnt do it while in the
garage they said they could find no fault but could order me a new
indicator stalk if i wanted one!!! (£150)

Its got really bad now and i cant really drive it. Got an auto
electrician to come and see it wednesday but does anyone know what it
might be so i can pre empt any conversation with the sparky so i dont
get ripped offbeing a girle and all!!Thanks