I believe I might have a problem in my basement with Carpenter Bees...I noticed a tiny bee at the top of my basement stairs the other day...and today as I was leaving my laundry room in the basement I saw a larger bee on the floor...they were both kind of sluggish so I could just step on them and kill them...they just seemed to be on the floor all of a sudden...are they "overwintering" from last year possibly?...where should I look for their nest or where they may be coming from...and what can I use to kill them myself...or should I have an exterminator come out?...Thanks