@RalphR. Excellent post, the rising rent indeed helps a great deal, didn't think about that. And indeed the numbers change. From what I hear around me the banks are still demanding fast repayment for rental property's , so I have no choice but paying off faster. During the crisis some people even got letters from their banks stating their mortgage needed extra payment because their total portfolio value of rental property's was higher then the current market conditions.
Even though they paid every month on time and rental income exceeded their total cost by a nice margin. Most flatly refused , and told the banks to back off. That's not happening any more due to the rapidly rising house prices.
If the economy keeps improving the banks will be a bit more lenient with their conditions. For now it makes it hard to get that excellent deal, a few years back it was possible but I didn't have enough money. Now I have and the housing prices went up a lot in recent years. But I will keep on searching and hopefully make my first buy sometimes next year.