Tim,
The solar panels on the roof are sized to handle the parasitic loads that exist in your coach (mainly from the ECM (engine control module) with every thing in the coach turned off. If you are storing the coach indoors, the solar panels obviously can not work.
The easiest solution for battery charge maintenance with indoor storage is to plug the coach into shore power if available. The inverter/charger will maintain the batteries on a 15A outlet if they are fully charged when plugged in. If your inverter has a power sharing feature, set it to 15A to prevent tripping the breaker on the shore power outlet, otherwise watch the coach a few minutes after plugging in to be sure that the charging current is well below the 15A capacity of the outlet before leaving the coach.
The other option is to remove the negative cable for the chassis batteries or install a manual disconnect in it to prevent the keep alive memory of the ECM from discharging your batteries. The decision will have to be yours, depending upon what resources you have available and what you are comfortable with.
Gerald