I'm not saying that she will have an instant solution for you, but a really good mortgage person will be able to give you "a plan" that's both realistic AND achievable.  

The instant gratification of living in the “cool” and “modern” apartment takes priority over making the fiscally sound decision to invest in real estate and begin building a passive income stream.The combination of wanting the best and limited mobility makes real estate investing an unrealistic and impossible option for many millennials.

I played Kiyosaki's Cashflow 101 game with her and she was instantly hooked.  

Don't expect this to be instant.

It could be a huge payday for them.

Hope it leads to a big payday for you.Bringing a developer along can't hurt.

It's tougher and can be a bit riskier(better be eating ramen for a few months), but your payday comes sooner and you could then repeat or turn it into 3-4 rental properties if you did it correctly.

Flippers like to work on a properties where they can make a bigger pay day at the end.

You are worried that you might sell the house for a big payday and would have wasted the closing costs on a refinance.

Airbnb hosts, assuming they don't turn on the 'instant book' feature, can accept or reject each guest.