I have the Magnum smart battery combiner, this is the way I would go when hooked to shore power.
http://www.lslproducts.net/ALS_Overview_Page.html
Here is one for less $$$$
http://www.rvupgradestore.com/SearchResults.asp?Search=AMP-L-START&Submit
JR
2006 Country Coach Inspire 360 40ft Genoa Designer Series Cat C9 Samsung 197 RR
Aluminum Radiator was recently replaced with a STEEL & COPPER Bolt Together Radiator w/ updated rubber mountings
SilverLeaf VMS 330
Toad--2011 Ford Edge Sport, Air Force One
:C