My understanding is anyone who enters Thailand on a Visa exemption entry needs to be able to show they have available at least 10,000 Thailand Baht for individuals or 20,000 Thailand Baht for a family..
That's is an immigration rule..
But in reality it's very rarely if ever checked or any questions asked about funds however it's still a possibility of course so you should be aware of that..
If you have traveled to the Philippines you will understand what it is..
It's a website or App where you must register your intention to enter the country before you travel..
It's only a proposal at the moment and the Thai government released some information about it in the media with a very optimistic date for implementation but that's already been postponed..
Just ignore it and there will be plenty of information about it once it's actually rolled out including a trial period where it won't be compulsory.
Use the Agoda hotel booking website or phone app..
You can search in your price range and read hotel reviews as well..
You can use filters for things like hotels with swimming pool..
Also has a map feature to check location..
Make sure you are walking distance to the beach and plenty of restaurants and bars.
Start looking around 1500 Thai Baht (about $65 Australian dollars) per night and see how you go..
There are cheaper options and many much more expensive options but that's a good starting point for 3 star hotels and you may even find a couple with pools for that price