I’m trying to calculate the cap rate on my own to see if it’s worth the investment. 

I have seen instances where clients convert to a two unit and the property is worth less than if they did a higher end rehab of a single family.best of luck!

That'll buy you $428,571 worth of real estate.

(One Airbnb client of mine outside Denver added a hot tub and barrel sauna and outperforms his competition by nearly 40%.)

I have clients who are interested in buying a flipped property but the investor didn't pull permits and added a bathroom.

No amount of money is worth you and your wife's safety.

Prob worth your time to get involved with that as well. 

And at no fault of their own – cashflow is what they were SOLD on.Here's what I want you to understand about “buy and hold” residential real estate:Let’s use a single family home with a property value of $300,000Let’s use an initial loan amount of $240,000Let’s use an interest rate of 7.25%And I’m going to give you $150 of cash flow per monthUse a 5% appreciation amount for your propertyLet’s see what happens after 5 years:After 5 years…$150 of cash flow per month = $9,000Your mortgage has been paid down to $227,000 = $13,000Your property is now worth $382,000 = $82,000So that’s $9,000 of cash flow, $13,000 of principle buy down, and $82,000 of appreciation.

I don't think about them much but take comfort in knowing that in 20 years, they'll be worth a lot more.

I'm not that professional but I think a whole house filter would filter particulates like dirt but not chlorine. for chlorine you might need a reverse osmosis system for a specific drinking water tap to eliminate the taste as it's not practical or efficient to put an RO on the whole house supply. if skin issues from bathing are a problem you might need a softener. sometimes when kids have eczema doctors actually prescribe "bleach baths" where a small amount of chlorine bleach is added to the bath water. also many of the water treatment systems can be rented so maybe just rent it while they are there. regardless, proceed with data. water test, pediatrician diagnosis (if it's legal to ask for, no clue), and a system that is right for the application. sounds like the tenant is willing to help out which is awesome.