4 Plex Landscaping Question - Plants, Dirt, Mulch or Other??

[Kyle Rosseau]

Hello BP Community, 

I have a 4 Plex pictured below.  I am tired a mowing the grass and the general upkeep (two small grass patches.  I have a landscaper to take out the grass but I haven't decided what to replace it with.  I thought some BP'ers would have some ideas.  I am thinking about doing a rock garden, super low maintenance plants or mulch.  Any other ideas??  I am really looking for low maintenance and cheap ideas.  The property is in Oakland CA so gets a lot of sun. 

Thanks,

Kyle