I'll be in WA from DEC untill the end of the summer.
right now I'm with a 9m HadlowPro and a TT. is it enough for most of the spots or should I add a 7m? (maybe i'll buy there a surfboard also)
I'm your weight and i go about 50/50 between my 10m and 7m. That said, a 9m will probably be fine, as long as you don't mind being fully powered up. The last two days here were about 24kts, i was well and truly on my 7, but there was still a few 9s and 10s out and about. If you're gonne be here for a few months then maybe buy the 7. You'll do more kiting with 2 months in WA then you will in a year over there...
I have an 8.5 and 10.5 and use the 8.5m 85% OF THE TIME IN PERTH. If your riding a twin tip then I reckon you cant go wrong with an 8 or 9. if your riding a surfboard then you could use a 7 most of the time.