Heirloom Hoarder

You will receive the chopper in the mailbox on the character you earned the achievement on.

Since patch 6.2.2, the reward is now directly added to your mount collection when the achievement is earned on one of your characters.

Greetings,

Note that the reward will be sent to you via in-game mail on the character that triggers the achievement.
Please note that this may take a few minutes.

Awarded for collecting 35 heirlooms and rewards you the [item=122703] mount, which is usable from lvl 1!
After patch 6.1, all collected heirlooms are learned and stored as a "crafting recipe" in the heirloom collection tab. This tab can be viewed on all characters and you can click on any heirloom to craft it into your bags - it will even be labeled with <Made by X>!

Heirlooms can be obtained in many ways, but are most easily bought from [npc=6566] (H) and [npc=6294] (A) for gold. Both vendors sell varies heirlooms, including the tokens that can be used to upgrade your heirlooms to scale all the way to lvl 50.

The heirloom prices are as following and are NOT affected by reputation:
- Chests: 500g
- Shoulders: 500g
- Necklaces: 700g
- Trinkets: 700g
- One-Handed weapons: 650g
- Ranged & Two-Handed weapons: 750g
- Shields & Off-Hands: 500g
- [item=122338]: 500g
- [item=122339]: 750g
- [item=122340]: 1,000g
- [item=122341]: 1,500g
- [item=151614]: 2,000g
- [item=151615]: 3,000g
- [item=167731]: 5,000g
- [item=167732]: 7,500g

Edit: Updated for patch 9.0.1 (SL)