I could see 300-400 but 1500 is expensive and not a drop in rate. People look at it as part of visa cost. The figure 18,000 + 10,000 for visa not bad. But you probably have to do visa runs not extensions. I think the annual cost with annual is expensive
The doctor or workcation is better deal. Especially if you really need doctor dm treatment away.
In HCMC city yes. Holiday and now weekend. They might be backed up next week. I would guess 10 business days. But book a changeable fare then you can leave when completed
Then apply. Might be risky but it doesn’t say you need to be married a specific period of time.
Your other idea. Apply then transfer to his account could work unless they ask in the future to see bank accounts. As of now not required if you leave every 6 months.