Query about buying second home and keeping first as rental property

I was talking to my friend during the week who said she plans to buy a new house next year and keep her current home and rent it out.

You might want to show her this Key Post

Should I keep my first house when I trade up?

Having another property with serious negative equity will make it very difficult for her to buy another house. She will have to have a huge deposit and very high earnings.

Brendan

Yes you are correct, you need to show you could afford to repay both mortgages yourself incase the rental is not rented out. Also like Brendan says negative equity makes it much much harder.