If PAw reports 100' below, target may be above or below, there's a 200' allowance in altitude reporting (so technically could be 400' out, but 200' in my experience)
If you're climbing or descending and get a 'Danger 200' above/below' without a 'Traffic' or 'Warning' before hand - it's YOUR Mode S/C it's seeing, don't sacrifice aircraft control looking for it (I'm not saying don't check)
Get used to the traffic reports on the ground and in the circuit, use it to build your SA (situational awareness) and familiarity with what the system is telling you