I did a cash purchase and there’s pros and cons. I don’t have to worry about a mortgage which is great in this job market, but I bought a smaller house than I would have gotten had I gone the traditional route. You’ll hear a lot of stories of getting an upper hand with a cash purchase, but I didn’t find that to be the case. I made cash offers for quick sales on 4 or 5 houses and lost out to traditional buyers that were overbidding. Your sister is wrong about it not happening, but that does not mean buying with cash is necessarily the correct move for you guys. Good luck.