each applicant in each name. Check with your embassy if you have a double-name bank account and if they would accept. If it’s in a spouse name, then the second person needs to move money to their bank otherwise can only be dependant and not get own DTV, but it varies from embassy to embassy so vetting info in a group is pointless, please check with your embassy.
The best of all is study for children, send them to school, then get Non-O Guardian based on the study, in the meantime you can also get Non-O ED for yourselves
But if you want to do the DTV then 500,000 for each applicant
Study for minors for example in Hua Hin can be as low as 5,000 per year per child