Why would a politician sollicit foreign investors to come and buy real estate? In the Netherlands we have a shortage of affordable housing. Especially in urban areas, especially housing in the price ranges affordable for young people and middle and low incomes.
This is pretty much a constant, of course now that the economy is doing well and the house prices are rising again, after the 2008 crises, it is even more true.
A couple of years ago - at a period in time when affordable housing was a scarce but real estate prices were not going through the roof - our then Minister for Housing was on television in Singapore asking investors to come buy ('invest in') Dutch real estate.

Here is a clip in Dutch, shown in a late-night show: "Starters op de woningmarkt - Zondag met Lubach (S09)"

Why?
Could there ever be any benefit for citizens when investors buy existing real estate? They are not building new houses.
Could there ever be any benefit in a situation where affordable housing is already scarce?
The owners of existing housing certainly benefit from increased demand and higher prices for their assets. The total benefit to society may be positive or negative, depending on whether current owners win more than current non-owners lose (from higher prices if they want to buy and become owners).

Higher price of housing makes new buildings more profitable, benefiting the construction industry.

The politician may favour certain groups over others, for example the construction industry is usually a large donor in election campaigns. So the politician may want real estate prices to rise even if it is on average bad for the country.

`Invest in' need not mean buying existing housing, but it could mean building new buildings and selling the apartments in them. This could increase availability and decrease the price of housing.