Gross Yield And Net Yield
Gross yield is the simple figure quoted in listings: a year's rent divided by the price. It ignores every cost of owning the property, so it always flatters the result.
Net yield takes off what you actually pay to keep the property let: weeks with no tenant, agent fees, maintenance fees, repairs and property tax. A home that is rented out is taxed at the non-owner-occupied rates, which start at 12% of Annual Value and rise to 36%. That is far higher than the rates for a home you live in, and it is often the largest single cost.
Annual Value is IRAS's estimate of what the property could be rented for in a year. It can differ from the rent you actually collect, so use the figure on your property tax bill if you have it.
If you have a loan, the interest reduces your cash flow further. The yield figures here are before income tax and say nothing about whether the property's price will rise or fall.