dual charging system and different battery sizes

Just bought 110W solar panel kit for camper with a dedicated 12VDC system run from a type 24 battery that is charged through an isolation solenoid from the vehicle alternator.  In connecting the charge controller to the battery, do I need to install blocking diodes so the alternator of the vehicle does not damage the charge controller?  Isolation solenoid in use now is wired to vehicle ignition so the camper battery is connected to vehicle charging circuit whenever ignition is ACC or ON.

Second question:  I would like to add a type 27  deep cycle battery (Recieved for free)to this circuit so I have 2 batteries for camper use. I believe the differences between battery types will adverse affect total battery life so I want to keep the batteries separate in both charging and discharge circuits.  What has worked for this type of application before?  Simple relays to switch between? or just big switches directly in the lines with operator skill required to prevent problems.  Bottom line goal it to keep the install simple and clean.  Any thoughts of a circuit diagram that would accomplish this.  I know just enough about electronics to be a hazard to myself    (20 yr navy engineer)