You can have many single entry permits as mentioned before but I would consider multiple entry as you still have a whole year of visa remaining so with your 2 important trips even if you fly (or take bus/train) to some nearby country twice then you will have your money worth anyways.
That sounds perfect! In case if after getting this visa I want to stay with my wife full time there do I just do the visa run every 90 days or in that case I need to show 400k in Thai bank?
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