Fitting a leisure battery to a Symbol

Hi from a new member.
We are relatively experienced motorhomers (?) but about to take delivery of a, for us, fairly new and shiny Symbol. Our previous van had a 120 watt solar panel and a hefty 2nd battery but the new van will have an 80 watt panel with no 2nd battery - am I worrying unnecessarily about draining the van battery? We tend to use ehu in this country but in warmer parts of Europe we often use aires and small sites which may or may not have power. If anyone out there has a newer model Symbol - where do AS put the 2nd battery? Under the driver's seat? 
Thanks for any thoughts,

Dave

I think you are worrying unnecessarily. We had an 80w panel and only one leisure battery of 90 amp and a battery-master on our Nuevo and in summer months we mainly use C&CC temporary holiday sites with no hook up leaving the van on site for up to 4 or 5 nights and never had dead batteries.

I have a 2012 version and have installed a second battery, the first battery was under the long bench seat making it a fairly simple job, if you are buying a 2014 on it may well be different so putting the year on your "new" van would allow a more relevant answer. I fitted on because I didn't have a solar panel at the time
David

Thanks to both of you for answering so quickly. it's a 2017 model so will have less as standard, which will help.

whoops, LEDs, wretched auto correct!

Hi, DaveW if you complete your profile , with your van model and year you will receive more advice tailored to your predicaments, Symbols have  evolved over time.