I started the process of buying a property in my home country in 2018. I payed my initial down payment and has not be registered yet. Can I have this in 2018 taxes ?

[Anita01]

If the property was legally yours in 2018, you could use it in 2018 if you had any deductible expenses like mortgage interest or property tax.  Down payments are not deductible.  Closing costs are also not deductible if you plan to use this personally.  If you plan to rent the property, you would not enter anything until the house becomes available for rent.