I called Jerry and heard a recorded message saying that he answers calls after his work day ends. That was helpful (indicative of his helpful nature in general, I think) because it let me know that he would, in fact, call that day. Luckily Jerry was able to call early, happened to be in the neighborhood, and so stopped by late that afternoon. When he arrived, Jerry installed a furnace filter, which was a simple task for him but not for me due to the furnace's tricky location. Then I asked him to check on a shower door guide. He couldn't fix it on the spot because the door was old and the guide was broken in half. However, he did make some helpful suggestions that I will follow up on later. (The door works as is, so it can wait.) When Jerry left, he said "no charge," because he was there for what he characterized as only a few minutes--and that he had been nearby anyway. I will definitely call Jerry again. He was a pleasure to deal with.