I frequently pass by an elderly neighbor who lives in the same apartment when coming home from a dog walk. He's kind of an in-house carpenter for the building and is frequently seen around the garage. I usually just nod to him with a small murmur that sounds like こんにちは.
Now this chap is not exactly as close as a family, so
ただいま doesn't quite feel right. But he's more on a talking basis rather than a higher-up, which rules out
ただいま戻りました. I've seen
ただいまです used in the Internets but not in spoken Japanese.
What's the appropriate words of greeting in this situation?