I have decided and already bought several new door slabs.
I have the jigs and tools to quickly and easily cut out the spaces for hinges and handles / locks.

One question that I have is what hinges to use...I went to HD and see several different sizes, like 2.5 or 3.0 inch....what would dictate the size of hinges I need / want ?

ALso - those are solid core doors vs. what I had previously (hollow core).
Since they are so much heavier - should I use 3 sets of hinges or 2 hinges are enough ?

Thanks !

 

I mostly just paint doors so I can't answer about the hinge size but I've seen no small number of warped 2 hinge doors, both solid and hollow core. I'd go with 3 hinges per door.

 

I use 3, 3.5" hinges on interior solid doors. 4" for exterior doors.

If you are using a router jig, you'll want hinges with rounded corners. The radius should match the router bit your jig uses.