I went to the monthly antique/flea fair here in my home town and bought a Speed Graphic 4X5 in a normal condition with some signs of wear, but apperantly in working order and with the lens with no fungus, scratches, etc. Even if the camera is not working fine, I can go to the fair next month and throw it at the seller .

First question is about the plain film holders, can I use it any one (from any brand) or I have to use only the ones from graflex?

Are the bellows real leather? If so can I use the same products for caring leather? What I have to look also to see if the camera is in order, besides the normal things?
Thank you!