The Islands are really good to visit and ferries are dog friendly, all Calmac Ferries have dog friendly areas to sit in.
There is a laminated copy in your holiday let, but perhaps print of one before you come to fold into a pocket. Please keep dogs on leads when walking through livestock and leave gates as you find them. There are loads of forest walks to do as well. I've listed a few of the forests that are near us but it's worth having a look at the Forestry Commission's website if you are going further afield or to check whether there are any restrictions due to forestry operations.
Fearnoch Forest - 3.1m (5km) away, along A85 towards Oban
Glen Nant - 4.2m 6.8km) away, head back into village, and take the turn off to Kilchrenan
Beinn Lora - 9.8m away (15.8km), take A85 towards Oban and follow A828
Sutherlands Grove - 14.7m (23.7km), take A85 towards Oban and follow A828
Barnaline - 17m (27.4km), head back into village, and take the turn off to Kilchrenan
Cruachan - 17.8m (28.6km), head back into village, and take the turn off to Kilchrenan
Glen Creran - 21.5m (34.6km), take A85 towards Oban and follow A828, once you've gone over the bridge at Dallachulish, turn right at the roundabout.