Can you raise rent on units at diffrent amounts?

[Ramon Mota]

Hi in October I took over managing 3 homes that I inherited.  In November I attempted to switch all of the units over to a new month to month. All but one signed the new terms and returned them to me. This month the one that never signed freaked out on me when I told them I was going to issue a 3 day pay or quit telling me rent wasn't due till the 9th. but the agreement on paper on file is the 1st. they did pay on the 15th. If the one unit I'm having trouble with is the largest 1400sf and also the highest cost to maintain. Can I raise that rent by a larger percentage than the others?

We have found that 2 of the three are well below market value on the rent.