Ghost Hunting Regrets

From my experience you can plan plan plan but once you get to an investigation it will always change. So I always end up going home saying "why didn't I do that"?  One example of this and the one that I still think about was our second investigation at The Rio Grande. Tim and I were there with our GhostBuster class and we were able to go into the basement in groups. We had already been there in fact just a few weeks before so we kind of broke off from the group in the basement and ended up by a telephone with no display on it and I could not see where it was plugged in. Tim had the Ovilus out and we kept getting phone phone phone. We would then hear a faint telephone ringing sound and then nothing for a few minutes. We noted it on our recorders and moved on down the hallway. About half way we got "go back", I asked where we were to go and we were instructed to go back to the phone. When we got back we got the telephone ringing sound and then we got a dial tone. I again examined the phone but never picked up the receiver. After going back and forth down the hall and back Tim and I decided to go back upstairs and let a few more people go down. Thinking back on this I kick myself for not picking up the phone receiver. I often wonder if I did would I hear someone on the phone? Did the spirit we were talking to have a message for us?  I will probably never know but the good thing is you don't  have to investigate places only once. We have been to some locations a few times now and I hope one day to go back to The Rio Grande and seeing if I can get the message via the phone.