If you have a space larger than a small closet, you'll fit a TD-4 or TD-9 kit in it easily.
3ft by 5ft, possibly less, is about all you'll need (including throne) for a TD-4 kit.
They're very compact.
Don't get an HD-anything if you intend on really having a good go at drumming.
They're nowhere near realistic in size and layout. The novelty will wear off quickly.
I started on a TD-4, went TD-9, added TMC-6, went TD-12, double TD-12 and finally (when it comes through) will be a TDW-20.
That's about every configuration (plus SPD-S, SPD-30 and Korg WaveDrum) so I'm speaking from experience.
As a minimum, TD-4 (kit) or nothing, is my advice.
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Kit: Roland TD-30; KD-120, PD-125(3), PD-105; VH-11, CY-15R, CY-14C(4)
Aux Roland BT-1, DP-2 Pedal(2); Hart Dynamics Hammer
Hardware: Roland MDS-9 Rack Tubes; Gibraltar 9606 SN, 9607-LD HH, 9608 Throne, 9611-DD Single Pedal; SC-4425MB Booms,
SC-RBA Tube Clamps, SC-EA100 Grabber, SC-700HA Tom Arm; SC-GCSRA, SC-GRSCTL & SC-GCHML Road Series Chrome Clamps