This may be heresy, but I think it's worth pointing out that in large format, lens quality is *much* less critical than it is in the 35mm world from which the OP is coming, because (1) the enlargement factor is so much less, and (2) typical apertures are so much smaller. (There's nothing unusual in the 35mm world about shooting a Tessar at f/4, where its technical limitations become pretty obvious. There are lots of Tessar-type LF lenses around, but it would be unusual to shoot them as fast as f/11, and good luck even finding one that goes to f/4!)

The point is, for exploring the format and discovering whether it works for you, BUY CHEAP LENSES. I just glanced at KEH's lenses in the 135mm range, and I would suggest, for instance, that the $199 for a 135/5.6 Symmar-S would be better bang for the buck than the $751 for a 135/5.6 Apo-Sironar. (Or the $2,699 for a 135/3.5 Planar! Holy @#$*.)