1 year advance in rent? with 3 months deposit??

No!!!!

In normal, just 3 months in advance and 1 month deposit.

Let's get you Llord's brain straight.

NOTHING, EXCEPT NOTHING, IS VALID FOR CONTRACTS WHOLLY WITHIN VIETNAM (i.e. not import or export) UNLESS EXPRESSED IN DONG. Even the VN government is bound by this rule.

It's the law of the land.

It is NOT STANDARD PRACTICE to demand more than TWO-MONTHS DEPOSIT + FIRST MONTH'S RENT.

ALSO ELECTRICITY MUST, by law, BE BOUGHT FROM EVN - ONLY - unless 'included' in the rent (i.e. a room - no meter).

Depending on the province, Foreigners get to pay HIGHEST WATER RATE rather than a tiered amount

Say to the Llord, if you rent, you HAVE TO PAY BY MONEY TRANSFER in to his bank account (VN law requires payments over (I seem to remember) equivalent of USD$3,500 BE BY MONEY TRANSFER. This gives you two benefits: (1) You know where your thieving Llord banks (and they have his ID); (2) You have independent proof of payment. When you make a deposit YOU fill in the DEPOSIT SLIP and YOU can state WHAT THE PAYMENT IS FOR.

I also love reading leases. Look out for Llord demanding YOU to VACATE EARLY (often 30 days) - make it SIXTY.

Is there a rental Agent involved? They must be crooks as well as they know the law.

And NO VNese don't do this or fall for these crooks.

For Nha Trang is quite common, but for sure not normal, up to 2 years. Even 10 years paid in full gas been done already (requested and paid). Especially within the tourist area and since a few month also some areas in the north. At this moment, the property market in Nha Trang is not only jumping, but rocketing.
This niveau will continue for at least a couple of more years until enough businesses are broke and properties stays vacant.

Nha Trang only has a small number of landlords and those now holding back properties and thanks to a growing numbers of inexperienced "Expats" from a certain country rents rocketing. Some restaurant owners pay well above the 4000USD a month for 3 story, 3x80sqm building in the prime area.

If you need/want to rent affordable, you will have look towards south (harbour), direction Honh Rho, just behind the old airport, or up north, well after the bridges. There are still some gems from about 300-400 USD a month but you also will find 2000 USD + a month (with 2 years in advance +deposits).

If you not have a local at hand, you see even less less property.

Place I was looking at is in Vinh Diem Trung in Nha Trang. Nice developed area with a new shopping center opening. But, can't find a landlord willing to rent 3 months in advance.

Read: Typical House Lease Contract in VietNam

That is a quite upscale area with the surrounding areas during rain season flood prone. Most of the properties in the center  having the same owners to.

Common or not depends on the owner him/herself. All are subject to negotiation. So, try to make use of your skills!