without knowing power requirements, i would suggest this. 6 channel's worth of rcas (front door, rear door, subwoofer), 16 (or 14) gauge cable for door speakers, 12 (or 10) gauge for subwoofer speaker wire. 1/0 gauge car audio brand cable (or 2/0 gauge welding cable, audio power/ground wire is oversize from true AWG spec). and remote wire cant forget that. all that should let you put a roughly 2000rms combined (1500rms on subs, 500rms on mids and highs) system in without connection problems. car audio wire brands to look at are stinger and knukonceptz. welding cable brands would be eb flex or royal excelene. a lot of people suggest sky high but i am not a fan of whoever their cable manufacturer is. any time i strip sky high wire the strand bundles immediately come apart and do not stay together when re-twisting. never had that issue with welding cable or other brands of OFC cable.
i cannot stress this enough but you absolutely want OFC (oxygen free copper) for speaker cable and power/ground cables. CCA (aluminum) wire is cheaper, but performs worse and cannot handle as much power compared to OFC, when comparing the same gauge sizes.