>>3313200If you don't mind a third-party flash (with TTL), you can get almost two Godox V860II for the price of a Nikon SB-700.
I have one and used it with my D3100 until I very recently got a D7200.
(if you find the V860II too big they also have the slightly smaller V350, both use rechargable Li-ion batteries)
Off-camera flash is also a breeze with the Godox system.