Viet Nam's Law on Housing (Law No. 65/2014/QH13) does not impose any restrictions on the number of residential properties that a FIE can invest in Vietnam. However, it limits foreign ownership to up to 30% of the total number of units in an apartment building and up to 250 residential houses in a ward administrative unit. The period of house ownership is 50 years as per typical lease term, with the possibility of an extension. 
"Article 3. Definitions:
In this Law, the following terms are construed as follows:
1. Housing is a work built for the purpose of living and serving the daily-life needs of households and individuals. [...]
3. An apartment building is a house with 2 floors or more, with many apartments, with common walkways and stairs, with a private part, a part under common ownership, and a system of infrastructure works for common use by households. families, individuals and organizations, including apartment buildings built for residential purposes and condominiums built with mixed-use purposes for residential and business purposes.
[...]
Chapter II - HOUSING OWNERSHIP
Article 7. Subjects entitled to own houses in Vietnam
1. Domestic organizations, households and individuals.
2. Vietnamese residing abroad.
3. Foreign organizations and individuals specified in Clause 1, Article 159 of this Law.
Article 8. Conditions for recognition of house ownership
1. Domestic organizations, households and individuals; for overseas Vietnamese, they must be allowed to enter Vietnam; for foreign organizations and individuals, they must fully satisfy the conditions specified in Article 160 of this Law.
2. Having a lawful house through the following forms:
a) For domestic organizations, households and individuals, through investment in construction, purchase, hire-purchase, donation, inheritance, capital contribution, housing exchange and other forms of other as prescribed by law; [...]
c) For foreign organizations and individuals, the forms specified in Clause 2, Article 159 of this Law shall be adopted.
[...]
Chapter IX - VIETNAM-BASED HOUSE OWNERSHIP OF FOREIGN ORGANIZATIONS OR INDIVIDUALS
Article 159. Subjects eligible to own Vietnam-based houses and forms of Vietnam-based house ownership of foreign organizations and individuals
1. Foreign organizations and individuals entitled to own houses in Vietnam include:
a) Foreign organizations and individuals investing in housing construction under projects in Vietnam in accordance with this Law and relevant laws;
b) Foreign-invested enterprises, branches and representative offices of foreign enterprises, foreign investment funds and branches of foreign banks operating in Vietnam (hereinafter referred to as foreign organizations and individuals);
c) Foreign individuals allowed to enter Vietnam.
2. Foreign organizations and individuals may own houses in Vietnam through the following forms:
a) Invest in housing projects under construction in Vietnam in accordance with this Law and relevant laws;
b) Purchase, lease-purchase, gift or inheritance of commercial housing, including apartments and separate houses in housing construction investment projects, except for areas ensuring national defense and security according to regulations Government regulations.
[...]
Article 160. Conditions for foreign organizations and individuals to own houses in Vietnam
1. A foreign organization or individual prescribed at Point a, Clause 1, Article 159 of this Law must have an investment certificate and houses constructed under a project prescribed by this Law and relevant laws.
2. A foreign organization prescribed at Point b, Clause 1, Article 159 of this Law must have an investment certificate or papers proving it is permitted to operate in Vietnam (below collectively referred to as investment certificates) granted by a competent Vietnamese state agency.
3. A foreign individual prescribed at Point c, Clause 1, Article 159 of this Law is permitted to enter Vietnam and not entitled to diplomatic or consular immunities and privileges prescribed by law.
4. The Government shall stipulate in detail papers proving the eligibility of, and conditions for, foreign organizations and individuals to own houses in Vietnam.
Article 161. Rights of house owners being foreign organizations and individuals
1. Foreign organizations and individuals prescribed at Point a, Clause 1, Article 159 of this Law may exercise the rights of house owners prescribed in Article 10 of this Law. In case they construct houses on rented land, they are only entitled to lease such houses.
2. Foreign organizations and individuals prescribed at Points b and c, Clause 1, Article 159 of this Law have the rights of house owners like Vietnamese citizens but shall comply with the following provisions:
a/ They may only purchase, rent-purchase or receive as donation or inheritance, and own no more than 30% of the number of apartments in a condominium. For individual houses, including villas and semi-detached houses, in an area with a population equivalent to a wardlevel administrative unit, they may only purchase, rent-purchase or receive as donation or inheritance and own no more than two hundred and fifty houses.
In case there are many condominiums in an area with a population equivalent to a wardlevel administrative unit or individual houses in a street, the Government shall specify the number of apartments or individual houses which a foreign organization or individual may purchase, rent-purchase, receive as donation or inheritance and own. [...]
c/ Foreign individuals may only own houses as agreed in house purchase and sale or rent-purchase contracts or donation or inheritance transactions for no more than 50 years from the date they are granted the certificates and may enjoy extensions under regulations of the Government if they so wish. The house ownership duration shall be clearly stated in the certificates. [...]
d/ Foreign organizations may own houses as agreed in house purchase and sale or rent-purchase contracts or donation or inheritance transactions within the term stated in their investment certificates, including also extended duration. The house ownership duration shall be counted from the date they are granted the certificates and clearly stated in such certificates;
dd/ Before the expiration of the house ownership duration prescribed in this Law, owners may donate or sell their houses to subjects eligible to own houses in Vietnam. Upon the expiration of the house ownership duration, if owners fail to sell or donate their houses, such houses must come under state ownership. [...] (Law No. 65/2014/QH13 of 25 November 2014, Arts. 159, 161 [google translation])
Law No. 65/2014/QH13 of 25 November 2014, Arts. 159, 161 [google translation]
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