The fourth of July is coming up and I planned a party at my apartment inviting family members from out of town and other friends over yesterday the 21st I got a letter on my door from the managers stating that if I have over four guest at my apartment they are requirinng a $450 deposit of which $150 of the money is non refundable. Are they allowed to charge me for have a party??

Check your lease. If there is nothing in your lease about a limit on visitors then no, they cannot charge you. But I wouldn't be surprised if its in your lease.

I don't remember seeing anything about quanity of vistitors that I can have but when I get home I'll check my lease