Option 2: Electrician recommended mini splits - said 2 units should do the trick and would cost around $6-$7k.Heating system 2 is forced hot air oil furnace specifically for the 3rd unit.

I would recommend buying a standard SFH with opportunities for an ADU, or a split floor plan where you could rent out the rooms!

BiggerPockets also has a calculator to analyze deals, and I highly recommend you start this as soon as possible, even if you are not ready to buy.

I would recommend that you reach out to a few and see who you like.

Has anyone used this device or have another recommendation to monitor water usage? 

I'd like to be able to give a variety of options for the listeners along your recommendations and feedback on the options.

Quote from @Brook Burns: Thanks so much for the recommendations!

Would really appreciate if anyone has any recommendations!

I recommend browsing Airbnb in your target zip codes to see what’s trending on the front page—this can give you valuable insights into what’s working well.

A good real estate accountant can save you thousands of dollars by leveraging entity selection and formation, tax deductions, cost segregations, bonus depreciation and tax planning.I recommend finding an accountant specializing in real estate taxation, business taxation, financial planning and tax planning.Consider working with your accountant remotely to expand your options.I would also recommend looking for an accountant willing to work with you throughout the year.