Jamberry is a multi level marketing company which sells a nail ‘wrap’ product (kind of like a polish replacement).
It’s relatively easy to find information about Jamberry, their company, products, and compensation plan. You can sign up on their site to become a consultant and they will assign you a sponsor if you don’t already have one.
Products are sold on their website, directly through their consultants via inventory on hand, through orders, or through the consultant’s website. Also, Jamberry consultants are known for hosting parties to sell the nail wraps and give workshops.
What does it cost to get started?
To begin selling Jamberry nail wraps as a consultant you purchase a starter kit. A starter kit costs $99 and includes application tools, business materials, samples, etc.
Additional Expenses 
It’s against Jamberry’s policies to create marketing and business materials, they must be purchased directly from Jamberry. Catalogs cost $6.50 for 10 and must be purchased with each new release (every 6 months), another site reports the cost as 25 catalogs for $14.50 with free shipping. In addition to catalogs there are also host join pamphlets, sample cards, postcards, order forms, and more.
To sell Jamberry online you’ll pay $10 every month for a website.
There are also additional costs associated with collecting money and running a business: credit card fees, tax preparation, etc.
For purchases, marketing materials, and direct sales you’ll also likely need to pay shipping and handling (including for your starter kit).
Do you need inventory? Can you just sell online and take orders?
You can just sell online. However, there is a lot of pressure to carry inventory. Most of this pressure comes from sponsors who benefit from consultants purchasing additional product. Additionally, much of the trainings and success stories revolve around parties where customers learn to apply the nail wraps and buy products at the parties.
Inventory held on hand may also go out of style as new nail wrap styles are released. Returns by consultants have limitations outlined here. Mostly, consultants may return only $1000 in any 1 year period, and may only return marketing materials upon resignation.
Encourages personally purchasing to meet quotas and get bonuses
Because commission structure requires consultants sell a certain amount each month ($200+, host a party with a certain amount of sales, etc), consultants may be encouraged to purchase a significant amount each month regardless of whether customers have actually made purchases.
This seems like a good idea because otherwise the consultant will lose access to higher commissions or bonuses. Additionally, they may be pressured for letting down their team or sponsor who may miss out on opportunities well.
This cycle of personal purchases to meet quotas can lead to debt, stress, and problems. Personally purchasing to meet qualified volume requirements is never a solution, ask sponsors for other solutions — introduce you to new leads, co-host an online party, etc.
Who is getting paid and how? Details!
Unlike some of the other programs Jamberry’s compensation plan is right on their site here.
They also publish the number of active consultants at each rank in 2015 here.
More here: Full Jamberry Compensation Plan
Consultants make commissions based on their personal retail sales volumes (30%)
Once they maintain $200+ in PRV (personal retail sales volumes) they can get additional sales bonuses (up to 10% more).
Consultants recruit other consultants to add “legs” and “downlines.
Managers and executives make additional “generational overrides” or commissions based on the PRV of the generations in their downlines. The number of generations they can collect commissions on depends on their own rank and team’s total retail volume, personal retail volume ($700), number of active legs, and more. The overwhelming majority of consultants never reach these ranks.
Jamberry consultants can make additional bonuses for moving through ranks quickly (“Fast Start Rewards”), advancing to each level (“Rank Advancement Bonus”), and more.
 This blogger does a good job breaking down the additional costs of becoming a Jamberry consultant and has some other posts skeptical of Jamberry.
Consultants at each rank and earning ranges (2015)