Lollipop Chainsaw

This one is pretty straight forward. First you need to earn enough medals to spend the necessary 10,000. There is a good guide to get medals under the "Millionaire Hunter" achievement. Look there first.

Ok, so now that you got your 10K medals, what do you buy? I would suggest starting with all the abilities and upgrade for Juliet. This should cover a major chunk of the 10K.
(Still working on getting all the exact numbers. Then I will format).

Health and Upgrades:

Magic Beans - 60
Crunchy Monkey Ceral - 90
Fruit Poot Juice - 135
Donkey Fruit Crepe - 205
Rodent Chow Mein - 250
Octopus Roll - 310
Sirloin Steak - 360
Toro Sushi - 410
O'Bannon Turkey - 470
Tofu Burger - 590

Power Dumbells LV1 - 70
Power Dumbells LV2 - 140
Power Dumbells LV3 - 550

Homing Sneakers LV1 - 60
Homing Sneakers LV2 - 120
Homing Sneakers LV3 - 480

Aromatic Yoga Oil LV1 - 80
Aromatic Yoga Oil LV2 - 130
Aromatic Yoga Oil LV3 - 510

Sub-Total: 4770 Medals

Awesome Skillz:

Nick Shake - 210

Cheerleader Chain - 100

Chainsaw Stab - 60
Chainsaw Full Swing - 140
Chainsaw Chain - 210
Final Chainsaw Power Attack - 740

Armadillo Spin - 120
Maelstrom Spin - 150

Lolli-O-Copter - 200

Chainsaw Paradise - 180
Jump Stab - 280

Zombie Grab - 170
Butt Attack - 210
Body Bash - 220

Chainsaw Drill - 300
Chainsaw Strike - 190
Brutal Cut - 300
Holy Chainsaw - 999

Sub-Total: 4779 Medals

Grand Total: 9549 Medals

Once you have all the abilities and upgrades, the next kind of items you are going to need to spend the remaining medals on are "Nick Tickets" and Lollipops. Now, this is the crappy part. Each of these items cost only 30 medals each, but if you are completely empty on both items, you will spend a solid 420 medals to stock up. In the end, a full stock up and buying a second round of "Nick Tickets" should put you over the 10 K.

At this point, you might as well just burn through the "Nick Tickets" and the lollipops. It doesn't really matter what "roulette" you choose, but some take longer to finish than others. To help speed this achievement up, TRY to land on the "Nick Shake" because this will provide extra medals. (This trick is explained in more detail for the earning 10K medal achievement, but I thought mentioning it here would help). I believe that there is a "fail" option indicated by a big red X, so if you can land on this, your "Nick Ticket" is offically burned. Then burn the lollipops. Rinse and repeat.

NOTE: It's a good idea to avoid buying the items that require platinum medals because I don't know if these will count towards the 10k. Even so, the platinum items are usually pretty cheap and that makes yet another reason to not buy them.

Just remember, if you are not finishing this achievement in one sitting, you MUST reach a checkpoint, otherwise every medal you spent will not count. So, if in doubt, just finish a level.