BritTim

Yes, you can. https://www.google.com/maps/place/Roi+Et+Immigration+Office/@16.0777263,103.5867843,15z/data=!4m5!3m4!1s0x0:0xa7c79c80224b712b!8m2!3d16.0777263!4d103.5867843

I am reasonably sure that, for non Lao citizens, you must be a resident of Laos in order to get a multiple entry tourist visa in Savannakhet. When the METV was introduced, that was the rule: home country or country of residence. I do not believe that rule has changed.

I am not sure if you currently have a multiple entry Non O visa or an extension of stay based on marriage. If you have a multiple entry Non O visa, you will receive 90 days, whether entering Thailand by land or by air. If you are exiting with an expiring one year extension based on marriage, you can get 45 days from a visa exempt entry. However, it would normally be better for you to go to Savannakhet or Ho Chi Minh City for a multiple entry Non O based on marriage to a Thai. None of the above rely on money in a Thai bank account. For a new one year extension based on marriage, you will, of course, require a Thai bank account with 400k baht.

It seems like the 1,500 baht will be for the Cambodian visa on arrival plus the same day return. They probably have you pay this separately in case Cambodian immigration decides to up their prices. With the current dollar/baht exchange rate, this is not far off what I would expect to pay doing it myself (assuming I cannot avoid the fee for same day return which I mostly have managed to do).

As already explained, you can only get two visa exemptions per calendar year when entering by land. With a visa, there are no limits to the number of times you can enter by land. The difficulty if wanting to stay indefinitely on tourist visas, will eventually be finding embassies/consulates willing to issue you the visas. Years ago, some consulates would issue unlimited numbers of tourist visas, but all embassies/consulates now have limits of one kind of another. With careful research, you can get quite a few, but will probably eventually run out of places to apply, certainly places where entering by land is somewhat convenient.

If wanting to return to Thailand by land from Malaysia, my choice would be: DMK (Don Muang)->PEN (Penang)->Hat Yai by bus->HDY (Hat Yai)->DMK The Sungai Kolok to Bangkok train is a really long trip (at least 20 hours, and sometimes more). For those with limited mobility, it would likely be very difficult crossing the border at Sungai Kolok, as no-mans land involves about a 1 km walk.

If you happen to run into a mentally defective airline supervisor who tries to insist that an onward flight is required, I suggest the following. Tell them that you are 100% certain there will be no problem arriving without an onward flight booking. However, just to satisfy them that the airline can have no financial exposure should you be denied entry, you will happily sign their indemnity form guaranteeing reimbursement of any costs that they could theoretically suffer.

Definitely preferable for many. It is worth mentioning that airports are not exactly relaxing. Depending on your immigration history, returning by air for a visa exempt entry can be nerve wracking. Immigration might deny you entry.

Cheapest border bounce from Bangkok at the current time is via Cambodia. There are companies that do trips to the border daily by van, which is convenient, slightly uncomfortable, and a bit more expensive than doing the trip yourself on public transport. One option, if doing it yourself by public transport is Ban Pakard (Phsa Prum on the Cambodian side). Take the first bus in the morning to Chanthaburi (about four hours and 200 baht or so), then local van or songtaew to the border . The van costs about 80 baht, as I recall; the songtaew is a bit cheaper. Either way, there may be a fairly long wait, and the trip takes a bit under an hour. You must leave Bangkok early in the morning as public transport back from Ban Pakard becomes iffy late in the day. Crossing the border, you must buy a Cambodian visa on arrival. Have US$ available to pay as otherwise you will be charged a lot more to pay in baht. You are likely to be asked for more anyway. My policy is to try to resist the request for extra money, being sure to do this in a polite and friendly way, but some find it less hassle just to pay up. The official visa price is US$30. By law, you are supposed to stay one night in Cambodia but, in practice, you can go straight back to Thailand. However, Cambodia immigration will likely want a monetary inducement to let you go. If asked, see if they will accept 200 baht, and (in a polite and friendly manner) resist a request for any more than 300 baht. Arriving back on the Thai side, ask around to see if there is a van going to Pattaya. If not, retrace your steps back to Bangkok via Chanthaburi. There will probably be agents on the Thai side wanting to handle everything for you, including the visa and same day return, for a premium (often almost double). This is less hassle. It is up to you. The cost (best case) would be about 400 baht Bangkok <-> Chathaburi about 150 baht Chanthaburi <-> Ban Pakard US$30 for the Cambodian visa on arrival about 200 baht for same day return (possibly avoidable) You might be faced with some unavoidable extra costs if things do not go smoothly. It is a long, tiring day to do it this way, and would not be everyone's choice.

You have already been given the most important information. Just to answer your specific question (though it is a bit academic) ... If you were denied entry, it would become Air Asia's responsibility to remove you from Thailand. Since you already have a booked ticket on the same airline, I cannot imagine the airline supervisor wanting to go to the trouble of getting you on a different flight, assuming you would only be staying a few hours at DMK.

As you know, it depends on what the OP meant by Non O. If he had a Non O multiple entry visa, this would remain valid until the visa expires. However, your assumption that he actually meant an extension of stay based on marriage is probably correct and, yes, that ceases to be valid on the day the divorce is processed.

It is reasonable that you have a limited time to acquire the visa once it is approved. However, the question was "how long after you have paid for a 10-year visa do you have to use it?"" This is similar to the question of how long you have to enter on a Thailand Elite membership once you become a member. It makes no sense to me that you would have conditions like entering every year, or entering the first time within a limited period.