Colleague willing to loan me $30,000 at compelling rate

[Steve S.]

I've never done this before. I would pay them back shortly (probably 6 Months or less) at a lower rate than a margin loan from my stock account. 

Whole reason for doing this is to avoid a tax event by selling stocks to pay for part of my downpayment

I have a couple of options  

1) they could pay me as I do some side work for him and he could 1099 me  

2) he could pay pal me and I'd pay him back over a couple of months (if I borrowed margin it would be about 8% so all of this is about saving me several hundred $$$). 

What is the appropriate way to do this in the most tax advantageous way?  His preference would be to somehow run this through his business if possible. 

Any thoughts? I'll talk with my CPA as well