Mailchimp also I believe is free up to a specific number 

This then will leave the property free and clear.

@Tom OchiengI would reach out to a real estate attorney for specific advice on this situation since you already have one tenant who is being difficult.On a side note, when I have inherited tenants, I have been most successful when I have provided longer non-renewal notices, like 60-90 days, and offered to assist with moving costs.

We don't believe they are stealing, but their negligence has cost us a lot of money.* Is this enough to file suit in small claims court? 

The reason not to upgrade, is that you won't get that much more income for the cost of the upgrades.  

Looking my insurance policy it mentions that I can opt for settlement under Actual Cash Value vs Replacement Cost. 

In southern CA, even garage conversion ADU additions are typically costing more than the value added.  

Is there any good rules of thumb to estimating the cost of a boiler?

Make sure to consult a financial advisor if necessary and also consider reaching out to your local credit unions.

You will incur more lending costs but you will only be in the first loan for 6 months.