Cheap printer means cheap thermisters. They are not very accurate.

When it comes to setting temps you have to guess it really.

eg I cannot print ABS at 230C I have to set it at 255C in order for it to melt.
This doesnt mean the nozzle is at 255C, it means my thermisters read 25C higher than the real temperature.
It is a huge inaccuracy, but that's what happens with cheap parts.


As for sticking to the bed, add a glass plate then use ABS juice in a spray bottle and spray a layer of it on the glass.
All of my prints, ABS and even PLA stick to it pretty well and not has a single warping issue yet!