HSBC can help you get checking accounts setup in almost any country.We are taxed on our world wide income in the US, but that’s not that big of deal, as we have treaties with other counties to help avoid double tax, and you can always setup up IBC in Cook Island, or St Kitts & Nevis, thus off shoring the income earned outside of the US, if you bring it home you will have to pay taxes on it.

I agree with @Joe Villeneuve,He's an Architect, and knows his stuff.I also did a mockup for a Class B SFH.Pushed out a wall, cut a doorway, boxed in the water heater (check local building codes re this), added pantry cabinets (at the expense of counter space (not everyone is full on cooking 3 squares a day, with the readiness of microwave and ready to heat oven foods.) 

I am also interested in flex spaces and storage facilities.

Here's the reason I love this area, and why we relocated here when the market crashed.Southern California:Strong, broad based economyPerfect year round weatherStrong property valuesHigh demandSome of the best universities, colleges, medical facilities, sports teams, recreation, amusements, beaches, shopping, etc. available anywhereGood property appreciationVacation rentals often provide strong cash flow, and demand top rental amountsQualified renters, buyers, etc. 

On the flip side though with gas if electrical goes out they still have a way to cook but this still isn’t enough of a pro to offset the worry.  

HiAre mailers the best way to communicate to owners of self storage facilities to express interest in buying?

Yes, based on the other facilities near by it will be mainly Class A RV's and Pontoon/Fishing Boats. 

Purpose of financing: We wanted to purchase the property to rent out the house portion and either rent out the store portion or use it ourselves as a store or some other type of income producing facility.

I am also looking for a good commercial broker/s to help me find self storage facilities in Washington State, Oregon, Louisiana, Idaho, and Montana.

I'll furnish more info on a self- storage facility I'm buying in FL.