Down there, making sure the roof is not blown off during a hurricane may decide whether a person will purchase your home or another down the street.

And then you have to do it again - one time - next month or however often you decide to print up flyers and hang/mail them.

How do you think they will feel if they realized that their electric bill is a higher because you decided to place solar panels?

This way your business and tax strategies are tailor-made to your needs/wants versus what the legislature decided.

The only thing that muddies things from your view is that HELOC only charges you for the interest calculated and you decide how much extra to pay. 

That lets me keep precise accounting of them and understand how that plays out for each property.  

The lender portion is your responsibility, if the lender just decides tomorrow they change their mind, it is not the sellers problem to deal with.I would agree with @Jason Hirko find something to keep them sticking with you if you are sure it is going to close.

@Jordan Troutman ok to estimate insurance when deciding what you want to do, but before moving forward, get some firm insurance quotes for your specific property and situation.

Government run economic agencies, The Chamber of Commerce, heavily experienced Realtors in that area, current Housing Associations, heavily involved Banks involved in the local financing may all be successful at helping you to find the right information you need that will help you decide on to what to do.  

Good Luck, would love to hear what you've decided and how it went.