Vietcombank does not charge for incoming wire transfers. I have three personal accounts at Vietcombnk. To date, I have not had a problem with upper limits on any transaction. Vietcombank will charge for transferring funds to third parties,. If within Vietcombank the charge is under VND 8,000 and for charges transferring funds to other banks it is about VND 12,000.
1) Foreign exchange account (mine is in USD) All funds coming from outside of Vietnam go into the USD account. If you wish to make payments for outside of Vietnam, the funds must come out of this account. If you wish to take cash out this account (my case USD), Vietcombank will do a double currency exchange. The first will be taking the USD out of the account at the Vietcombank USD-VND exchange rate and then make a second conversion back from VND to USD at the Vietcombank exchange rate, then you get the cash. If you need the foreign currency for local use or if you are leaving Vietnam with cash (as long as it is under the declared value), you can get the cash in VND from Vietcombank and have it exchanged through a local money changer or other party that handles these types of transactions at a better rate. Check the rates prior to conducting the transactions as these rates are constantly fluctuating.
2) VND account. I transfer from the USD account to the VND account for living or other expenses I may need. There is no charge for transferring between your accounts. If you are not a Vietnamese citizen, you can not deposit money into the VND account except from your foreign exchange account. The only two exceptions are payment you may receive from local payroll or local contractual payments such as consulting fees. However, you will need to furnish relevant documentation to Vietcombank before they will accept the transaction.
3) Investment account, USD. Any investments you wish to do such as in the equity markets or into a specific investment must first be deposited into the investment account. The funds are then disbursed as per the legal documents such as an Investment Certificate, that are relevant to the investment. At a later date, principal and profits can be deposited back into the investment account for expatriation. You can invest in many opportunities using VND without the hassle of using the Investment Account, but you loose all you expatriation rights on the funds.
I also have a Visa card issued by Vietcombank that I use regularly with no problems to date, for purchasing items from outside of Vietnam or paying for services outside of Vietnam. I also use the card extensively for traveling expenses and cash withdrawals while I am outside of Vietnam.
Banking regulations will drive you crazy in Vietnam. Use a good bank that has many foreign customers. Don't open your accounts in a local rural branch that has few foreigners. If possible go to the main branch.