Any modern digital minilab will usually print direct from 35mm and 120 slides and give excellent results, the price should be no different from a similar print from C41 films. After all they are scanning all the negs before printing anyway.

However if the minilab is analog (still using an interal enlarger ) then an interneg is needed.

Unfortunately larger format s can't be scanned yet by digital minilabs, but they can print from CD etc if you can get the slides scanned.