The kit comes with a set of hex keys.

Precision screwdriver set. (Philips and flat)

Must have.

Flat head set.

Comes in handy.

Small socket drivers 4m, 5.5mm and 7mm.

Must have.

Get two sets of hexagon socket drivers.

With these sets you'll work a lot faster.

Comes in 1.5, 2.0, 2.5, 3.0 and 3.5.  You won't use 3.5.  Try to find 4.0.  I haven't been able to find one.  4.0 is used on the head.

Must have.

5.5mm open wrench from Minicopter.  PN# 707.  Very handy in tight spaces.

Must have.

Straight and bent needle nose pliers

Must have.

Ball link tool.

There are various models.  This is probably a luxury model.  But it helps...

Must have.

C-clamp pliers.  Specialty tool.  Only used to remove the belt wheel for maintenance and repairs.

Good to have.

Light oil.

Blue Loctite.

Use this on all metal on metal screw contacts.

Must have.

Epoxy (J-B Weld)

Good to have.

Rotary tool.

Very handy.

Utility knife.

Must have.

Digital caliper.

Must have.

Long metal ruler.

Good to have.

Pitch gauge.  This has been fitted with a digital angle finder. 

This particular model also accommodates blades with a wider chord.

Luxury.

Blade balancer.

This is a luxury model.  There are less expensive ones.

Good to have.

Soldering iron.

Must have.

Helping hands.  Good to have during soldering.

Good to have.

Wire stripper

Must have.

Heat gun.

Luxury.

Heat shrink. 

There are packages that you can buy with multiple sizes and colors.  Long sizes are also available.

Good to have.

Drill & bit set.

Must have.

Sandpaper (400)

I used this to sand down the edges of the carbon fiber frames.  Safer for handling the frames and for the wires.

These sheets are approximately 8" x 11".  Comes in packages.

Optical tachometer.

Used for setting the head speed.  You could take your heli to an RC shop and have them do it for you.

Luxury.

Infrared temperature meter.

Nice to have.