Private Lenders- how to set up legally?

[Alexander Pezzutto]

I am considering using private lenders to invest in already owned property to pay off what is owed on a credit line used as the down payment. The credit line has about ten months before interest is charged and thus allows time for investors to pay into an already existing investment.

Should I meet with a lawyer and draw up terms of agreement for them to sign? Do I have to stay in regular contact with them? What if they want to withdraw their money?

Just want to see if my potential plan has problems or if they can be worked through. 

Thanks for your help :)