For the trailer if at all possible get a DEEP CYCLE battery, NOT a Marine/Deep cycle but a True Deep cycle, these are either golf car batteries or I think Wal-Mart now sells a "Trolling" battery that may well be Deep Cycle.
In wet cells TROJAN is best,, In AGM LIFELINE,, Howver I do not think either is worth the added cost.
Sam's Club, Costco and Wal-mart all give more bang for the buck.
You also have a choce
Flooded wet cell
NOTE: in 12 volt batteries you may have problems finding flooded wet cells.
Flooded are lowest cost, but they are highest maintenance, they need cleaning and watering often Properly cared for they last longer
Maintenance free are slightly higher in price, Low maintenance (NEVER no maintenance) you can not water them. Slight lifteime trade off
The above batteries all must be mounted "This side up"
AGM, has teh additional advantage of not having a THIS DIDE UP sticker
LIFELINE brand can accept a very fast re-charge (Compared to others)
OPTIMA brand (Also AGM) has a lower capacity and thus is NOT suitable for house use.
Home is where I park it!