If a foreign resident wants to purchase a property, then the money will need to be channeled in to the country via a special SIA (Securities Investment Account), held at a local bank. Once the property has been sold, the money can be taken out (plus any gains) via the same account in the currency that the money was deposited in. If you currently own a property where the money hasn’t been brought via a SIA account (eg. inherited, bought while a citizen of Sri Lanka), then there’s an annual limit of $20,000 when taking the money out of the country. You could still take the money out at once, if the source of the money can be proven to the bank and Central Bank (this whole process will take a few months to complete).
The government will allow $45,000 to be brought in to the country without declaring the source (Budget 2017)
The budgets of 2017 & 2018 have proposed that foreigners be allowed to borrow money from local banks for the purchase of condominiums (up to 40%).