exit from Transnistria (or both). Despite official orders from President
Smirnov to act professionally and to decline such payments, bribery is rife and
your passport may be destroyed if you do not pay. Indeed, you may be turned
away from the border on the Moldovan or Ukrainian side if you are unwilling or
unable to pay the border guards a bribe. To avoid this ensure that you are not
obviously carrying hard currency (therefore stash it away in carefully
concealed areas on your person) as the border guards will check you thoroughly
for it.
Having said that, most visitors these days visit the country with no
problems and are not ever asked for bribes.
Mind that the combined bus/train station does not have a luggage depot