There is no specific point. You can apply for a licence on any visa status. It will depend on your local department of transport as to what time frame they can do it in. Some take months.
That’s a question you’d have to ask them specifically. It would vary office to office or possibly case by case. Someone’s experience of getting a few days early or later would be irrelevant for your specific situation.
You’ve got some wires crossed somewhere. You don’t pay 500 baht per day if you fail to report a 90 day filing. You could be subject to a 2,000 baht fine if late but that’s whether you’re 8 days late or 80 plus days late.
There is no one year tourist visa for Thailand. There is a 6 month multiple entry tourist visa that you can eeek out almost 9 months from. There are conditions to getting that but a one year lease isn’t one of them.
The Thai Privilege Visa is a glorified tourist visa. It’s expensive but works for many people who don’t care about the price or value the peace of mind it offers.
Many are opting for the DTV visa as it offers a 5 year validity at a fraction of the price. If eligible check out the LTR Visa. It offers some tax benefits and is only 50k.