Once you find a house that you believe would be a good rental, meaning desirable to your target market of customers (people within a couple of mile radius of the place), and all of the costs of monthly ownership that you can accurately project fall below the rental amounts that you project that you can get from your target customers, then you have a possible business asset that you can use to produce income, and have renters pay down the mortgage, while hopefully it goes up in value at least with the rest of the economy. 

You could take that same $70K plus what you planned for that $680K down payment and buy 3 investment rentals in states like FL, TN, IN, OH, GA, LA, even up on the Oregon Coast just above you in CA.Most of my customers live in CA and none of them invest in Cali instead they buy in the states I listed above.

Legal documents and customs are tricky in a native language let alone a foreign one.

The cost of labor and materials now is insane.The type of work on my custom house is about 400 a foot.

there is a ton to being a GP syndicator raising 3 to 5 mil 50k at a time.. you now have 100 partners and the amount of oversight  customer care and Risk in my mind has to be considered compared to what you do now which is build sell and make nice bucks without being beholding to anyone but your construction lender. ??

If you want to run a charity by all means run a charity but don't speak such insanity that letting customers STEAL is ok, it's not.

I focus a huge amount of time on tenant screening and providing exceptional property management/customer service.

An AC unit in beaucoup Hot weather may have an up charge from the installer because he knows he can get it from customers who want immediate cooling.

Personally, I find that buying is usually quicker and cheaper upfront, while building offers customization but requires more time and coordination.

For example, if a family is displaced due to extensive water damage that will take a few months to repair, the insurance company will then look to find temporary housing for their customer/displaced family.