Can I legally ammend a lease?

Ok lets say I have a lease for an apartment (student housing) for $500 a month. Assume that I got these rates during a promotion, as normal rates are $550 a month.

Am I allowed to ammend the lease such that the difference (or atleast a portion… have to remain competitive) goes to me?

Example:
Normal rates $550 / month to landlord
My rates: $500 / month to landlord
The person I transfer my lease to: $550 / month ($500 / month landlord $50 / month me)

I see this as no different than buying a car for $200 and selling it for $300, only in the case of a lease I did not “buy” anything, rather I own the “rights to buy” something (the right to pay $500 a month).

It seems legal, but are there any Fluther lawyers who can confirm. Also how would I go about doing this??

The lease is totally transferable, but for a fee. I hope to pass this transfer fee to the next person in the form of higher rent (well current market price rent), or get extra cash if I can get them to agree to pay the transfer fee.