If you can go deeper than 7 feet then by all means go for it, but if you can only dig it out to the legal 7 foot ceilings then it's still worth it since like you said in your location someone will rent it for $1300.

Quality help is worth waiting for.How do I file an extension?

But worth it if you want to build a steady flow of discounted properties.

Likely not worth it.

It is worth consideration in making your property pet friendly, so that you can capitalize on the reality of pets and charge extra for them, as well as possibly make your home more marketable on the various hosting platforms.  

However recently I wanted to try some social media ads or ads in general and see if they are worth it.

It's human nature not to factor in their time, nor large episodic real estate expenses etc.almost forgot this table chart from Mary Callahan Erdoes , she is the head of JP morgan asset management which has hundreds of thousands of high net worth investors, They are quite stringent when comparing their own investor's returns to other Asset classes

I remember walking out of the bank with my heart fluttering thinking where is this money going? 

If the home is only worth $365K you cannot refinance to take out any cash and switching to conventional will only increase your rate so there is no tangible benefit to a refinance from current to Conventional.You are sitting at around 90% LTV if the value is $365K so a refinance would still require PMI and rates are higher than your 5.70% right now even with a rate buy down. 

The property is now worth $80k.