You may have a problem getting a consistent look with stain, since you have doors of several different ages and types. If you want an aged look, you might try milk paint.

There is a strong trend to imitate aged walls and doors, but not sure how practical this really is with your doors. You may like that each is different to create an eclectic look but it will require some very nimble decorating to work with this style ... Plus check for lead paint

What if I leave them as close to natural as possible, I was thinking different doors throughout the house would be fitting as long as they are authentic? Do I need milk paint if they are wood and after removing the lead paint (hours of hard labor) they are at natural state. Even have the porcelain door knobs and one has the crystal knob.

Stain them. They will be beautiful!

I think different doors would look good if they look nice and cleaned up.

Check youtube for DIY videos on how to clean them up.

If like an old farmhouse/rustic type look, they could add a lot of warmth and charm even if they aren't carbon copies of each other. I would try to stain them, and call any inperfections in how the wood takes stain the 'charm' of the door. That's what I tell my husband when we have something we're working on that isn't perfect. We want a rustic look to our home.

I grew up in a Victorian house. One summer my parents decided to strip, sand and re-stain the dozen or so upstairs doors. Off the hinges and into the basement they went and us kids were all conscripted to help refinish them. Our doors looked just like yours and were beautiful when all of that old lead paint was gone. Some parts of the doors were slightly darker or lighter than other parts but all of the doors were that way so they all went together. The challenge though was re-hanging them. It was an all day process to figure out which door fit in which frame because building codes didn't exist when they were built. So I guess, keep that in mind when you buy old doors; not every one will be square, often they are slightly different sizes so they won't necessarily fit in a modern standard jamb and lead paint is the norm. The upside is that they are really pretty when they are refinished. Best of luck to you!

I had this dilemma in the past when I was renovating a very old house for a local investor who was going to flip it. What I ended up doing was using a heat gun to get off all of the 130+ years of coats of paint off of it...then I lightly sanded the door...being very careful NOT to damage the designs in it...then I ended up staining them with a walnut stain and a few coats of glossy clear poly. In addition I found old hardware for the doors, cleaned them up, gave them a fresh coat of glossy black and the doors were completed with very old, but in good condition, round marble door knobs.

I did end up keeping one of the original doors that was never painted since the client wanted something much more efficient. I'm actually thinking of reusing this door, cutting it down to make into an end table.

Your going to want a contractor that has a good door supplier. The jambs will all have to be very custom and will drive some people crazy but that's alright haha. They might be milk paint already and not led paint. Might get expensive but reclaimed wood.

Sorry my browser cut me off. Reclaimed wood jambs would look amazing with these doors!

Old doors are almost always of a very good quality. I used them number of times as a pocket doors. If they did not warp in 100 years, they probably going to survive quite a bit more.

If YOU like the way they look as is, then use them as is. Otherwise, decide if you would rather have them stained or painted. Which would go best with the rest of the woodwork in your house?