I don't know - the hidden reserve has always bugged me - if someone has a minimum, I'd just as soon know up front and then if I still am interested, I'll bid. Maybe I'm missing some kind of psychology there... When I've really had a bottom line price I want, I've always just set the initial bid at that price, or close to it. In that case, I've often found that you don't get bids till late in the process, so it can be a bit nerve wracking, but if that's your lowest price, you'll see if someone is willing to pay it. You can always re-list if it doesn't go.
As suggested by Mudcat, you can also set a Buy it Now price at a few bucks higher than your starting bid, too.
"GAS never sleeps" - Gil Janus
"Now you got to pay your dues. Get that axe and play the blues." - Spudman
Gear: Epiphone Sheraton II, Epiphone Wildkat, Epiphone Emperor Joe Pass, Fender MIM Strat, Tacoma DR-14, Johnson JR-200 resonator; Fender Super Champ XD amp