Premium items only thing to consider.. Hard to obtain and the import costs, inefficient dealer / supply chains, and small local market make the prices crazy high.
Generally I just pay the extra baggage fees and hand carry everything or book it as sporting goods on the plane.. Some of my airport arrivals have been comical.
Things are cheap in Thailand ?? Really ? Not luxury things !!
When I came I imported 10s of 1000s in audio gear,. projection cinema back 25 years ago when that wasnt budget like now.. High end gear..
That stuff is multiples of the cost here than in the west. B&W speakers are 1.6 million baht from B&W in bangkok !!! Cheap ?? Not for the premium things.
Sure theres frustrations and pain points.. But over time they also get to know you (I order stuff from overseas I cant get here constantly) and if it comes to customs (not fedex / dhl / courier) can generally get it at a 'reasonable' rate.
Theres no clear rule that you can feel sure of. When I came (a long time back and on a marriage visa) I had everything correct to qualify for tax free import, they didnt care.. Even when I printed the rules in Thai and gave hime the proof it was duty free he simply refused to look at the paper.. They have your stuff and can ransom it back based on what they feel its value is.. Thats the simple reality. You are asking for black and white rules in a grey world !!
In my case it was a week long argument, with the final straw being him looking at 7500 USD worth of marble audiophile speakers and saying 'maybe we need to crack those open to check inside'.. 🤣 Its a long and funny tale but cant be bothered to type it all again.
That said generally a clearance agent is more expensive than the bribe, I got my bribe down from almost 100k to 15k cash to the big boss at lunchtime (that way he didnt have to share to the underlings). Many times people say 'I didnt pay anything my agent cleared it' and then it turns out the agent fee was 40k or 50k.. Where do they think that money went too ??
if I worked here I would be doing it. I know it doesn't give much, but it's an investment in long long stay.
But the vague processes, the way years may go by without any processing and the way some get fast tracked with no oversight or system that you can be sure of timelines etc is just off putting.