Should I buy it? Flip and hold Multi

[Jim Pintchuk]

I have been watching Northeast Ohio listings and jumped on my first potential deal, a 3 family bank foreclosure. They just dropped the price by $15k to $60k. I saw the house today. The good news is, it's a zoned 3 family in a nice neighborhood. It has a total of 4 bedrooms 3 full baths and a 2 car attached garage. All separate entrances and separate metered utilities - except water. The basement has a kitchen one bedroom one bath, unless I convert the attach garage to a master bedroom suit. People like the garage in snow country - not sure. The First floor has a kitchen, one bedroom one bath and second floor small one bedroom one bath no kitchen. This area rents a 2 bedroom for approx $700. Taxes are $2200 a year. The foundation and exterior are pretty good for a house built in 1908. Except it needs a roof. With laundry, the garage and a nice rehab, I should easily be able to get $1100-1200 month in rent. 
 The bad news is it pretty much a total gut job. Bad floors and walls in multiple places. A bathroom was stolen. Boiler heat with most of the piping missing. I think it should be fully gutted. If we go with High Efficiency Gas furnaces and duct work I can take out two chimneys and greatly improve the layout. It's a if expense.
My son and I (partners) made a verbal low ball offer significantly below the $60k asking price with $10k cash earnest money. My only contingency will be title search. I should hear back from the bank via the real estate agent early next week. I worked on my comps which are scarcely available in my area. Best I can guesstimate without better comps is the ARV should be around $120k maybe a little better. I'm trying to be conservative. Best I can figure my reno costs are around 60k. Multiple furnaces, a roof, three full baths and two kitchen remodels. When it's done we should have a small equity or break even and have virtually a new place with few problems and good rent potential.
If we mortgage, after rehab for $120k, with 20% down my payment will be $454 mth @ 3.9%. Even at $1100 a month that should leave plenty of room for taxes, repairs, and 10% or so vacancy to still turn a profit. Holding costs for a year during the Reno, with no renters should be about $10k. So, even if my rehab cost goes higher than expected, my long term cash flow from this property should be reasonable. We will do a lot of the work ourselves. I am a licensed Electrician. At least with a full Reno you don't have manny hidden surprises inside the walls. Sorry for the long message. Bottom line is I think this is a great location for us but a marginal deal. I'm willing to pay somewhat more for a multi unit place, in my area. They are few and far between. If they reject my lowball offer I probably won't come up much, if at all. Any advise from you, my new Bigger Pockets friends, would be greatly appreciated.