12v items hooked up with 24v setup

[NJSquatch]

For the additional $100 I would get a 3rd battery for the 12V appliances.

Having the 12 volt appliances running from the 24 v system will result in an uneven drain on the one battery shorting the life of that battery and the series. 24 volt systems like to have the batteries at the same state of charge. The TM might also pull the voltage way down on the 12v side under full power causing your FF to power down.