HELOC for down payment?

[Jon Hilfiger]

Has anyone used a HELOC on their primary residence to finance their first biggish deal? I found a decent deal that works with a 20-25% down but when I factor in paying back even the minimum on the HELOC (1% of outstanding balance) the numbers go south quickly. Key numbers:

42 units, $1.6M sale price; EGI - $234K; Expenses - $122K

There's room to reduce expenses, do some value add and tick up the rents overtime...So, thoughts? And...is this too big a swing for my first commercial deal? Thanks for any thoughts.