Dear seniors seek your help to understand the features of "Contract Employment"

I am in the HR dept. of an electrical trade company into the business of marketing of Fans & water lifting pumps. As during salary negotiation time every candidate is interested in more cash in hand, I wish to propose to my Mgmt. to start with contract employment too for the reason that to my limited knowledge on subject I know that on contract employment term there are no annual benefit & statutory benefits applicable and whatever monthly fee/salary is agreed is all cash in hand to employee.

Before I propose, I wish to understand the subject of contractual employment better and would appreciate if any of you could aid my learning on following points-

1.  is there any upper limit to duration of employment on Contractual basis? Like 12 or 11 months etc

2.  Can a contract of employee be renewed immediately for another terms (of same no. of months) on expiry? I.e. if contract of 12 months expires on 31 Jan'17 then can it be renewed w.e.f. 1 Feb'17 for another 12 months?

3.  How many times contract can be extended or renewed?

If you can suggest some site which can help me enhance my knowledge on contractual employment then please suggest so.