I here in the Netherlands Rotterdam working on renovating a 3 unit building

Im currently networking to partner up with a home builder here in Staten Island and build Semis on empty land.

Condos don't appreciate at the same rate as single family homes, and you are always a newly elected board away from STRs getting banned in your building. 

Our team buys the properties and converts them and manages them so it has been a great learning experience seeing all three phases from taking down a project, renovating the building then managing the lease up.

For path #2, you mean purchase & renovate a 3-5 unit building right?

We want to purchase a property to begin building our rental portfolio but are unsure of the best approach.We live in Sonoma County, California, and I work in Healdsburg.

@Robert Ellis Since you mentioned panels, have you looked into SIPs at all for your builds? 

You'll need a solid proforma and to build a team with expertise.

I would notify her in person and in writing (big note on her door) including quoting the clause in the lease where she is responsible, and tell her you will be inspecting to insure the heat remains on, high enough to protect your unit, or she will be breaking the terms of her lease and also liable for any damage done in the downstairs unit as well.

Build a team of professionals, prepare your finances, and carefully select a property near high-demand areas like hospitals or corporate hubs.