I am not opposed to making this my primary method of income either.

In this case it might be more of a 20/65/15 to get what you need out of selling the 1st. 

Any advice on some additional improvements that could be done to potentially fix this problem without having to buy a new water heater?

I'm going to follow this to see what tips folks provide.MikeHey Mike, I am actively investing there so feel free to reach out with any questions!   

The changes that have occurred in the past year is making sure the comps are truly there, getting the material costs down (or accurate) number with changes all the time on costs. 3.

But I’m thinking of getting into STR investment and become more active.I’m a complete newbie to short-term rentals (STRs) and eager to wet my feet in this area.

This number carries over into the two replacement properties.You don't mention capitalized improvements so I have to assume that your adjusted cost basis in the relinquished property is $230k. 

@Jesse Simmons  I did a similar deal as this in the past. 

If you’re interested in discussing this further, please feel free to message me.

I'm just gonna leave this here...