What do I need to know for a spontaneous visit to Thailand regarding hotels, entry documents, and health insurance?

Hello lovely folks.:)

I'm planning a visit to Thailand but it's very spontaneous and I dont have much time to find out everything necessary. It'd be an awesome help if someone who has been there recently could help me out. What's the best option for a hotel you picked in Bangkok - cheapest yet nice, and how much was it? How much do the tests on day 1 and 5 cost?

Mainly, do I need to have all the documents ready to show at the moment of entry Thailand or before that (while purchasing the ticket or departing from coubtry of origin)? As I'm do I have to apply for anything in advance?

Which insurance did you use, do you need to have it for the whole time of stay? Do they require to see your onwards/return ticket? The visa is free, upon arrival and up to 60 days right?

Just to confirm, documents necessary upon arrival are insurance covering min 50.000 for Covid related expenses (is 5hat in usd?), purchased Acom for first night and then the night from day 5 to day 6 (or from day 4 to day 5?) and that's it right. Or how did you arrange the transport from airport to ur Acom, also do they check that too?

I know it's a lot of questions but I'm sure it might help others too. Thanks everyone who takes the time to answer that.

Thanks a lot! ❤️