A good multimeter with all necessary functions. Two minor drawbacks, both related to response time: Firstly, the continuity tester has a short delay (0.25-0.50s) before it beeps - this can be annoying when trying to analyze a device with a lot of cables, or when it is difficult to maintain contact for a long time, leading to many false negatives. The other is that autoranging takes forever to scale down low voltage/current/resistance cables, on the order of two seconds in most cases. These aren't critical points, but it's certainly a benchmark for hobbyists/enthusiasts like me who can afford to wait and/or retest in the situations described.
Autoscanner for car diagnostics Rokodil ScanX Pro, OBD2 scanner
29 Review
MUCAR CDL20 OBD2 Scanner - Check Engine Code Reader And Diagnostic Scan Tool For All OBD II Protocol Cars Since 1996, With O2 Sensor, EVAP System, And Smog Test Functions
23 Review
Vgate ICar Pro Bluetooth 3.0 OBD2 Code Reader | Scan Tool For Torque Android To Check Engine Light & Car Faults
19 Review
Precision Bike Torque Wrench Set for Mountain & Road Bikes - Pro Bike Tool 1/4-Inch Drive with Allen & Torx Sockets, Extension Bar, Dual Readout, and Storage Box
11 Review