Ok now with a picture we can start to figure out a few things. So you think it was built aroun 1860. Seems very possible. Could even be older. Where is it? Just the state would help some.
What is the floor plan. Is there a central hall in the front portion? Looks a little narrow for that put camera angle could be deceptive. If there is no central hall then the front portion would be referred to as a hall and parlor. And it is regardless definitely an I house with a rear wing ell, a very big one at that. No central hall plans tend to be earlier than the ones with the central halls, but that is in no way an absolute rule. Lots started without a central hall and then a wall would be added to create one, if there was sufficient space. The style of the staircase could help date it as well. The simpler and plainer it is, generally the earlier. But again, not absolute. The pocket book of the original owner was always a facter in how fancy, just like today.
Not a fan of vinyl here but you didn't do that so won't say anything beyond its to bad but some things can't be helped. The replaced windows hurt in trying to date it because the style of the original windows tell you alot about when it was built. But again, can't be helped.
It looks like a VERY nice place, and huge. Tho I am guessing its basically one room deep so it may look bigger than it really is. Lots of old places tend to do that, the one room wide deal allowed for lots of cross ventilation in the pre air conditioning days.
As for researching it, you need to go to the court house and starting tracking it back through the grantor grantee indexs to see who owned it over the years and what the deed says about it. You might get a good idea of who and when it was built from that. When I got mine on the register we had to trace the property back to the royal land grants in the 1740's. Its all public records. Hopefully the records are all still intact and not lost over the years to fires floods or invasion(a real problem if you're in Virginia or Georgia and a few other places).
The vernacular farmhouse works for me as to a name for the style, tho it is a bit of a catch all. Can't think of anything better for it.
Locust Quarter, circa 1770 Georgian Gambrel roofed cottage.