With the specific paper you mentioned - Bergger neutral tone - I've gotten very nice cold tones via fresh Ansco 130 developer followed by a variation of GP1 gold chloride toner. The look is similar to classic old Seagull G graded paper, but without the hint of purple-brown (which could be introduced by just a tiny bit of selenium toning following the gold toning, if desired). Gold toning is not necessarily expensive. Most formulas waste gold like crazy. I mix my own. You only need about a quarter strength of the old published GP-1 version, and just enough to cover the print with tray rocking. Longer toning time will make up for less concentration. It has to be discarded each session.
The irony is that successful gold toning for coldness is most effective if the developer itself trends a bit warm. Hence 130.
Going straight to a cold tone developer like Amidol with benzotriazole, or certain MQ tweaks, won't actually give as rich a neutral black as the method I've just described with neutral tone Bergger paper, or even with a true cold tone VC paper like Ilford Multigrade Cooltone (an excellent product in its own right). But if you do go the amidol route, make sure its the high quality European amidol, and not the cheaper Chinese variety, which is contaminated with something discoloring. For those in the US or Canada, Artcraft in NYC has good amidol.