After my interview with Unisource, I wrote them a follow up email thanking them for their time and expressing my interest in the position. They thanked me for meeting with them, and said that they'd "like to continue the recruiting process, and to please send two references."
So I sent over two professional references, along with a professional letter of recommendation from my previous employer on top of that. They made me wait forever while checking my references, so I called to follow up since they were taking so long. They said they couldn't get a hold of my previous boss, even though I had provided them with the professional reference letter. (Which should have been sufficient by itself.) I completely went out of my way and called my previous boss and told her that I was seeking new employment, and if she could please give them a call. So, she did.
A couple of days later, they emailed me saying that they ended up going with another candidate who "more closely matched the qualifications of the position." They completely wasted my time, AND my references!! Now I can't use my previous boss as a reference again. I do not recommend interviewing or working with Unisource!