£16, that's a high starting point....
I totally understand your confusion as to the wide range.
There's obviously the bottom end of the market, shall we say under £8 on the ebay price scale....
At the bottom end of the price range, it's probably not got a replaceable fuse inside it and the quality of manufacture will be poor, bad soldering of circuit board etc.
A fuse is inside because if you make a mistake like setting it as a Voltmeter and connecting for Amps, the fuse will rupture instead of frying the meter....
Then there's whether to get Digital or Analogue.
Digital is quick and easy, but is poor at detecting pulses or flicks of supply, the display will just average out, whereas an analogue display, with a needle, will usually clearly show a pulsing needle ....
For your purposes, basic supply checks, resistance and continuity checks, a Digital should be fine.
I've noticed that the lower end these days tend to be AC Current or DC Current, but not both.
So make sure you get one that can be used for DC Current, which is usually limited to 10Amp (But some are only 5A).
You won't be checking the output current of the Dynamo/Alternator with that, or the cranking Amps of the Starter, but it's useful to have for checking the current drawn by individual circuits, if you wish to.
Auto power off is a useful thing to have, after you've left it on for 10 minutes or so.
Personally, for the sort of thing you want, I'd go between £10 and £15, in a good chunky case, it should be a reasonable quality for what you need..
This is by no means a recommendation, but see this one as an example. There's even a download of the Instruction manual available on the website to take a look at before you buy....:
https://www.espares.co.uk/product/es174 ... ultimeter- £
AC current: 2mA - 10A
DC Current: 2mA - 10A
AC Voltage: 200mV - 600V
DC Voltage: 200mV - 600V
Capacitance: 200µF - 20nF
Resistance: 200 Ohms - 200M Ohms
Continuity 'Bleeper' Function
Test Lead Length: 660mm