For the sake of full disclosure, I did spend a little extra on gold plated banana plugs and high quality shielded rca cables. That being said, I bought them all off ebay, so the per unit price was low compared to local audio stores.
All my systems are connected using the following banana plugs, both on the amp (yes, the amp supports plugs) and speakers:
https://www.ebay.ca/itm/8Pcs-Gold-Plated-Musical-Audio-Speaker-Cable-Wire-4mm-Banana-Plug-Connector/283217051058?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
Audio cables:
https://www.ebay.ca/itm/2RCA-Male-to-2RCA-Male-Audio-Cable-Gold-plated-For-Laptop-HDTV-DVD-VCD-Amplifier/173624214584?ssPageName=STRK%3AMEBIDX%3AIT&var=472302581645&_trksid=p2057872.m2749.l2649
For speaker wire I purchased 100feet on sale from Amazon for cheap:
https://www.amazon.ca/gp/product/B0...sin_title_o03__o00_s00?ie=UTF8&psc=1
16 gauge is perfect unless you're running big runs across the house. The nice thing about these amps, is you are never running cable that far because they are so compact that they can be placed anywhere.
If you want to save money on speakers, kijiji or craigslist has tons of great speakers for peanuts. I purchased my Energy ESM2-MKII's for cheap. They needed a little rebuild love. I got some Paradigm Titans in great shape for $40. The list goes on.