It's ONE person, that's all, check with ASLOCA. This 3 person requirement is purely myth, the law is very clear on this point for once. Providing you furnish the name of one person, suitable and finacialy able to bear the cost and who is ready to sign a contract, you are off the hook.

If a contract is presented to this person who then declines to sign, you are back on the hook.

Financialy able is usualy determiend as the rent and cost as being no more than 33% of your salary.