ORIGINAL: redvtr1000
Skids (both the landing gear and the skids) The skids themselves are changeable and I havent broken any through use, but if you follow the manual and place glue in this area for the training gear then good luck reusing them if you break the gear itself which has happened)
Blade grips - oh and more blade grips, I keep like 3 sets on hand and replace a set when I break them or make an order.
Spare flybar
1 spare canopy. Fitment isnt so great, always rubs on the main gear and sometimes tears in this area during impact. Also where the grommets are down low has a tendency to crack through and then you have nothing to hold it on well.
Main gear
Spare hardware set, nuts screws etc this stuff likes to play hide and seek
Spare linkages and control arms off servos (these like to bend and I have just been bending them back until one finally breaks.
Most commonly replaced parts for me are blades, grips, shafts without a doubt
Regarding the skids and landing gear. Instead of using any kind of adheasive, I just use tiny zip ties. They work much better, don't really add any weight and if your skids break, just snip the little buggers off.
The canopy. I notice that as well. Either trim some of it away or just cut slots out where the main gear is so it doesn't rub on it. On the bottom holes of the canopy, I just slip them through the pin without the grommets. I've never had a problem with it coming off. On the top ones, I got rid of the rubber ones that came with it since its usually a pain trying to get them through the pins. I had some tubing, very similar to the one that you use to hold the foam balls on the training gear, cut little pieces of it. I put one on the pin first, and when I put the canopy on I put one on the outside. Holds it nicely and keeps it away from the main gear. The one from the training gear isn't a tight fit, so you need to get one with a smaller diameter.
Good luck with your flying and have a great day.