Buying a Multi Unit Mixed use property

[Clive Owen]

What pitfalls am I missing...

Property is built in 1900 had 2 owners in past 25 years, just put on new roof a few years ago..... Would want contractor to look at it first (can that be contingent on deal if I make immediate offer...if he finds major problems walkaway I know you can for residential but commercial is a different beast to me) selling for $439,000 4 apartment units 3/4 rented at $850/mo + electric...water, trash included in rent and store front (empty) I would lease

mortgage rate is 6.8% for 15 years with commercial lender they offer other products... 3/1, 5/1, 7/1 ARM products as well as 10 and 15 year fixed. (3/1 ARM best rate is 6.00%) If rates were to drop 3/1 ARM would probably be best but fixed is easier to calculate

taxes are $6,000/yr

Ins I ran at 1.5% $6,500 because I'm unsure at the moment and it's a weekend 

Total comes to $3100/mo with 20% down 87k using paid off rental as cash out potential will update with rate hopefully Monday morning

I would be using a paid off rental property SFH as collateral, renter has been there 11 years never missed a payment worth around $150k at 80% LTV 120k leaving 30k equity for repairs/payments/closing costs would be at lower rate update Monday morning hopefully

I still have income from my full time job 36k/yr before taxes...lucky enough to be able to pay everything on wife's income both houses at foreclosure and auction and I put everything in retirement accounts Roth IRA's both/real estate investments I say this to state I have no bills