Keep in mind, buying a pre-construction unit and waiting a few years before it is done, already gives you an opportunity to watch the appreciation in equity depending on market conditions. You are buying the unit at today's price and locking it in. Therefore, the price in a few years would be different than it was today already!
Typically, depending on market conditions buyers like to either assign or rent out their investments.
An assignment is a sales transaction where the original buyer of a property (the “assignor”) allows another buyer (the “assignee”) to take over the buyer’s rights and obligations of the Agreement of Purchase and Sale for a proft, before the original buyer closes on the property (that is, where they take possession of the property). The assignee is the one who ultimately completes the deal with the builder.
In other words, an assignment clause allows the buyer of a home to sell the place before they take possession of it.
In Ontario, assignments are more common in pre-built homes and condos than on re-sale properties, but they are possible on any type of trade.
Another option is to simply rent out your unit and build more equity over time depending on market conditions. The equity you build after can be used to refinance and use that money for re-investments or whatsoever.