Need BP thoughts on potential first mixed-use property deal

[Alvin L.]

Happy New Year everyone! 

I'm new to real estate investing (haven't bought any properties yet besides my own single family home) and I'm fairly new to BP but have been reading tons of posts, bought and read the BP "How to invest in real estate" book, also met with several real estate investors, all of which has taught me a great deal. 

I've found a multi-use property in my local area that is currently asking 800k, I've run the #s several different ways and it can be anywhere from barely worth my time to extremely worth my time. 

Some background info on the property:

• Mixed use property
• 1 retail storefront (currently a deli) - 3 year lease - $3k/month rent
• 4 residential units averaging ~$1500/month/unit
• there's also a 2nd building on the lot that has violations on it, currently has no C/O. But was previously a 2 family building, which brought in ~2.5k/month total. This is now boarded up by the DoB so is being passed to buyer to deal with. There are potential assessments/fines associated with this that the buyer (me) would be liable for as well. 
• Taxes 45-50k/year with the potential of going up significantly (shouldn't exceed 6% in a single year)
• Heating PBO = ~$2500/year
• water PBO = ~$1000/year
• electricity for common areas = $500/year
• Asking price $800k

Here are my calculations, assuming 25% down payment, 800k purchase price, no estimated repairs (although this is wrong, since i'm sure I will have to fix a number of things for the building with no c/o), but I have excluded that building from the income calculations except for scenario B, where I assume i'm able to add $150 rent/unit and a modest 2k rent for the 2nd building.

I've also been informed that this will not qualify for conventional loans because it's a mixed use + over 4 properties. As such will have to resort to commercial loan it seems.

If anyone could share their opinion, thoughts, and constructive criticism, it would be much appreciated.

Thank you!