Does this make sense?!

[Chris Jackson]

I want to give some stats and my idea before I make a verbal offer on a property. If anybody reading this could double-check my ideas and let me know if there is a better idea out there, I would be so grateful! I do not have any capital right now, as this will only be my second investment property, so I am hoping to convince the seller to owner-finance the down payment. I know there are some assumptions in my math, but I'm making it as close-to-reality as I can:

8-plex (commercial financing)

Asking Price:                                      =                                                                                $290,000

Down Payment: 25% of 290,000       =                                                                                   $72,500

Mortgage of 217,500:     5 yr loan, amortized over 20 yrs @ 5% =                                           $1,435

Second Mortgage held by seller of 72,500:  5yr balloon, 6% interest-only payments =           $362.50 

Gross Monthly Rent  ($55,000/12)                                                                                =          $4,583.30 

Monthly Insurance/Taxes + Prop.Management (1833 + 275)                                       =          $2,108 

RENT - EXPENSES (2 Mortg.+Insur.+Tax+Prop.Manage)    4583.3-3905.5           =        +$677.8/mo

This does not seem like a very good deal to me.  Did I mess something up?  Or maybe my numbers on the monthly taxes and insurance are wrong?  Well... I'm going to go get more information but since I took so much time typing this up I'll go ahead and post it to see what you guys think. I guess what I'd really like, since I'm not sure about those numbers anymore, is whether there is another/better strategy for getting me into this commercial loan deal other than having the seller finance the down payment?

Thanks!