1. yes get a cover, can be a full boat cover such as what Overton's sells.
2. Cannot answer this question. You need to measure how wide the door opening is vs the max width of the trailer at the tires. Also how long the rig is (trailer tongue tip to prop) vs the depth of the garage bay.
1997 Silverton 362, 7.4 Crusaders
1997 2400 SCR, 5.7 Vortec / Bravo 2