Sure could use some advice

I've always gotten my dogs as puppies and have NEVER had a hard time training them but my dog Boo (the rescued one) I got at 1 1/2 and I am really struggling with a few thing.  First off...I love him, he's a snuggle bug and I won't get rid of him no matter what but his marking and barking are driving me crazy!!!!  I got advice on here about a water spray bottle for barking.  That kind of works but you must have the bottle with you at all times which is a little inpractical.  He barks for absolutely NO reason.  Any other ideas?  The marking is also bad.  He wasn't neutured when I got him and I had it done right away but he was already one and 1/2 years old and was used to marking.  Please tell me there is something I can do!  I should mention that I don't care about him marking outside but it's the inside (furniture and plants) that I could seriously do without.  Please pass some advice my way !!!!! Here's a picture just because (Boo's the brindle one).

http://i64.photobucket.com/albums/h180/slwhiste/CIMG2646.jpg