KARMEN

On a regular basis all of us use to find out shops and stores in our area which uses simple paper to issue bills instead of or issuing a proper bill. You will not find any account books or detailed records in respect of their Sales, Purchase and Stock.

But it doesn't mean that they are tax exempt. They have opted the composition schemes, by which they pay a defined sum in lieu of tax and be tax compliment.

A particular type of taxpayers always find it difficult to completely fulfill the compliance requirement oft ax laws, due to their small size or area of their businesses. May you be one of them. Also the cost of recovering tax from these types of tax payers is dramatically more in percentage then the tax recovered from them. But it doesn't mean that they didn't need to pay tax.

Although to complete this dual objective of simplicity for tax collector and tax payer, A specific Composition schemen is provided to Tax payer, by which the taxpayers can pay their taxes based on calculations on some parameter in lieu of tax calculated according to complex calculation expected by that law.

The same your will find Section 8 of Model GST law.

What is Composition Levi

[Notwithstanding anything to the contrary contained in the Act but subject to sub section (3) of section 7, on the recommendation of the Council, the proper officer of the Central or a State Government may, subject to such conditions and restrictions as may be prescribed, permit a registered taxable person, whose aggregate turnover in a financial year does not exceed [fifty lakh of rupee], to pay. in lieu of the tax payable by him. an amount calculated at such rate as may be prescribed, but not less than one percent of the turnover during the year. 
source:- gstindia.com]

The Scheme as per Model Law

Aggrregate annual turnover of Rs. 50 lakhs are proposed to be made applicable for the taxable person. 
The amount must not be less than 1% of the turnover during the year. 
The services or supply provided in inter state will not be eligible for it. 
Tax will not be collected by the such eligible person on supplies made by him. 
Any Input Tax Credit will not be entitle to any claim.

- Full Analysis of Feature of the Scheme. In section 2(6) have a complete definition of aggregate turnover, To mean aggregate amount of all taxable and non taxable supplies, exempt supplies and export of goods and services of a person representing a Same Permanent Account Number. 
- In lieu of Goods and Service Tax not less than 1 % of the turnover will be payable. 
- It is still unclear that whether the amount will be calculated on aggregate turnover or taxable turnover. 
- No tax will be collected by the Taxpayer on the supplies made by him. Suppose he has not to collect tax on the supplies made by him, so imagine him to be issuing sales invoices or maintaining a record of his turnover is a wrong thinking. 
- Input Tax Credit can't be claim by the Tax Payer.

Conclusion 
- Service Tax and State Vat Laws as on date has the availability of composition schemes. Different suppliers will pursue different kind of Scheme. So the schemes need to be developed by taking the nature of business in mind as compared to the size of business. 
- The value of Input supplies in terms of Supplier of Goods, the amount of composition levy needs to be fixed as expecting these suppliers to be maintaining records of their turnover is expecting impossibility. 
- The percentage of taxable turnover will decide the amount of levy not the percentage of aggregate turnover otherwise it will be very unfair to suppliers having non taxable and exempt turnover.