After my application for the apartment, they sent me an approval with an issue of "bond" 90 dollars, what is the bond? Why I have to pay for this, they never told me about the bond?
How do I know if they are charing this for no reason or not?

What if they are tripping? Trying to get more money from me? I have a good credit card score and I don't owe a cent!!

Thanks,

Could just be a deposit for holding an apartment for you pending signing a lease. Why haven't you asked them?

This is non refundable bond. I asked the leasing consultant that works with me on this apartment. She said there are some standards I didn't meet.

I have years of renting apartment experience and I don't have any debt plus my monthly salary is very good. I don't believe I need to pay the bond.

What you believe and what the management company requires are different things. You are certainly entitled to a detailed explanation of what the bond is for and why its required. But the consultant gave you the bottom line. After reviewing the application they felt you didn't met some of the standards they have set for tenancy. Most likely, these standards have nothing to do with credit rating and ability to pay. Probably these standards are elatively minor so they decided to approve the application but are requiring the bond as additional protection. I would say they are within their rights to do so as long as you aren't being discriminated against.