The city we invest in has a rule that anything over 1" depth must be cleared within 24 hours of the first accumulation, so we may be taking care of snow more than once per storm.  

I am trying to get a decent estimate so I can see what price I would need to pay for this house to get a deal done.Any help would be really appreciated, I am sure someone out there has dealt with this type of thing before.  

I started thinking how much I would want to kick myself if I purchased a property now but could've waited and got it for possibly ~20-40% less (just a quick estimate).

Scott The Book on Flipping Houses, The Book on Estimating ReHab Costs http://www.biggerpockets.com/flippingbookConsider checking out HUD homes for small multi's owner occupied gets first crack.

I'm trying to get some estimates lined up by Monday.  

I ran some numbers myself and although your repair and maintenance estimates are a bit low - I doubled them in my calcs - I also added the vacancy rate of 7% cause I always like be more conservative in my calculations - further more , to be sure its a good deal , you really should add the management fee cause otherwise you are making calculations based on you always managing the place yourself - ( which you may plan to do anyway ) however - I like to calculate what the cash flow would be if you had to walk away from the day to day operations and bring in manager   -  That being said - It looks like you are looking at roughly 934/ Mo in cashflow or $11,220 a year yielding you about 15.6% Cash on Cash return the fist year  - not a bad deal at all.

That averages to $19,600 per property as the target re-sale value.There will be closing costs to factor in on the re-sale (estimate another $15,000)Plan is to market them for a little over $1m (for 51 units plus a garage, that's damn good!!)

From what you say, the agent has a higher estimate of what the bid should be than you do in every case.  

When I accumulate enough equity, I would eventually like to be able to liquidate these and replace them with multi-family residential.Is this possible?

Scott The Book on Flipping Houses, The Book on Estimating ReHab Costs http://www.biggerpockets.com/flippingbookYou might consider Niche or Specialized Housing like student housing.