If you choose to extend yes. However, I will be leaving frequently through the year and each entry will get the 180 day stamp. I will stay nowhere near 180 days, perhaps closer to 80, will be absent for 30-40 days, then return for another 180. A Multi-Entry visa has no limit on the number of entries.
The Royal Gazette publishes the prices. The visa is 10,000 baht. The extension (it's not a renewal) is not specifically mentioned. All extensions of stay are 1,900 baht. It's been that way for years.
No requirement that you have to show you're "making a living" from anything. I have a registered business with an ABN, which means I'm a business owner. I can channel money through it which I make for managing my property and sharemarket portfolio. The "business" is located in Australia whilst I'm retired in Thailand. But I reckon I can become a "digital creator" like 75% people on Facebook! 😆