As long as he purchases at least as much as the investment allocation from the sale. 

Aesthetics won’t be an issue and it will pay dividends in the long run with eliminating landscaping/lawn and water costs.

If you think it is a great house in an upcoming area, you could offer a bit below market value as long as your cash flow numbers work.

Almost got a place in Tuscany back in Feb but couldn’t quite come to an agreement on deal terms. 

We've come to realize that the Boston market is too tough and the numbers don't make sense (to even house hack), so just recently, we decided to hone in on Plymouth, MA... with the idea that it could be a good tertiary market to do furnished rentals (thinking short-term/AirBnB in the summer, and mid-term in the offseasons).

Overall, it could lead to a more cautious approach to buying and selling, with more emphasis on long-term holds rather than frequent exchanges.

Yes, it's a 10-year declining dependent up on your term length and amortization period:  What You Should Know About SBA Prepayment Penalties | Pursuit (pursuitlending.com)

Yes, as long as the LLC is a single member LLC that is disregarded (does not file it's own tax return) then the taxpayer is the individual and the taxes are filed using their SS#. 

I want to buy a new private home and use my current primary residence equity (plus some cash) to buy a new primary house cash and then sell the old one.So, I am looking for a HELOC with little to no closing costs, as I will retain the money only for as long as I am selling my old house after buying a new one.Any advice?

The other option is to form an LLC prior and both go on the loan in terms of dual borrowers so that the land is used from one owner and the assets or cost to build is coming out of the other partners funds.If you do not own a primary home you can build a home with as little as 3.5% down but cannot use an investor for that option.