I find their note offerings to be on the expensive side, so have not bought anything from them.

If it ends up being an expensive or time-consuming repair, you may be able to get bids and have the seller escrow 1.5x or of the bid cost to do the work post-close with a signed agreement and lender approval.  

If you are worried that lender might close the HELOC, draw all the max and put half in a short term CD and other half in checking.HELOCS did get closed in the crash of 2008A standard full doc refinance should have $3000 of hard costs plus impounds which are not really a cost, just on going expense.

Why would the purchase be a business expense? 

If its a business expense, and the business is registered here in the US, it maybe able to work.

One thing we have noted as troublesome for some potential househackers with this conventional program is that in order to use rental income from the other units towards qualifying you need to have some current housing expense verified (rent, a mortgage, etc.) 

Good work is expensive but cheap work will cost you a fortune.

I've included an example below to help illustrate this.So different lenders have different rates (which do vary even for DSCR loans) but these are factors they all consider.See example below:DSCR < 1Principal + Interest = $1,700Taxes = $350, Insurance = $100, Association Dues = $50Total PITIA = $2200Rent = $2000DSCR = Rent/PITIA = 2000/2200 = 0.91Since the DSCR is 0.91, we know the expenses are greater than the income of the property.DSCR >1Principal + Interest = $1,500Taxes = $250, Insurance = $100, Association Dues = $25Total PITIA = $1875 Rent = $2300DSCR = Rent/PITIA = 2300/1875 = 1.23DSCR lenders generally let you vest either individually or as an LLC.

That could be expensive , if you are tying in to natural gas at the street , 5 grand and up . more if they have to cross the road . 

If they use hard money lenders those loans are EXPENSIVE loans because they are short term loans with no early payment penalties and they will also finance rehabs.