Duplex - 40k - Underestimating repairs?

[Dyanne C.]

First deal, I'm sure I made some mistake, thus the post!

Duplex - C Neighborhood 

40k - Purchase Price - 25% Down ~10k

4k - Closing

6k - Roof Repair

1.7k - Misc Upfront repairs

Monthly Expenses/Income

Unit #1 -  $450 - Currently rented

Unit #2 - $450 - Vacant

157.40 - Mortgage

129.17 - Taxes

90 - PM

60.42 - Insurance, although this might change

66.67 - Water

90 - 10% - Maintenance and Capex

90 - 10% Vacancy

45 - Lawn Care/Snow Removal 

Net Income - 171.35

The initial inspection showed a few issues, biggest ticket item being the roof which I was already aware of so I decided to proceed. Insurance company that first gave me a quote decided to not insure the property due to it having 60 Amp service and Knob and Tube wiring. So I'm currently shopping around for another insurance and I'm not sure if I should now add the electrical/upgrades to the list of repairs on the home. As it is now at least the property cash flows.

Should I include the costs of upgrading the electrical in the deal analysis? This was something I hadn't even considered at the beginning (because I'm a newbie and didn't know to look for it). Seems like it's something I'll have to do eventually to make the house easier to sell down the road. Or maybe it's unnecessary?

Also the house was constructed in 1900, so is 10% too low for repairs and capex? 

Any feedback is greatly appreciated! Thanks! :)