What do I need to know about entering Thailand on a visa exemption after traveling to Cambodia?

Hi guys, need assistance on 2 things as per updated terms as I haven't been back to Thailand in a few years. During our stay we planning to head to Cambodia for a week, just not sure about the travel between with regards to exit and re-entry. Coming from South Africa so trying to figure out if the visa exemption will allow it or if we'd need to apply for a tourist visa before band.

Secondly what is the required amount per person in USD apon arrival, last time they didn't check with regards to funds but did provide hotel info and will do so again if they need, just want to be extra sure on the funding side before we head out incase they ask on arrival.

Much appreciated in advance 🤞🏼