Power supplies (fixed and variable), O'scopes, DMMs, Function generators, logic analyzer.
Breadboards, perf boards, soldering irons, lots of misc parts (resistor, caps, pots, etc).
Fully equipped machine shop (drill press, lath and mill with all accessories). CNC if in the budget.
3D printer is now a must.
Software for schematic and PCB (Altium Designer), 3D mechanical CAD (Solid Works with all the optional packages), Programming IDEs: assemblers and compilers for all the popular processors and PLDs plus the hardware programming and debugging tools.
Should be able to put a good lab together for between $250,000 and $1,000,000 and maybe a quarter this is one shops for used.
This is just a basic list and doesn't include many details.