check the box and see what all is mapped to the breakers.

Defintely NOT a deal breaker or a reason to NOT buy. 

It runs on either the furnace circuit or A/C circuit.

Somebody that really wants to get in can still do it, but it might help provide peace of mind for tenants.Those size A/Cs will run on a regular 120 V circuit, but you might look around to make sure there are outlets close enough to all the windows you want to put them in. 

I think that is always recommended and it is something I do.My inspector has uncovered things they werent aware of and has also alerted me to issues to monitor to make sure they are rehabbed properly (for instance ensuring that the electrical scope included adding additional circuits because the current number was deficient).

That would definately be a bonus but not a deal breaker if not.

To create a Checkbook IRA you will need a facilitator company (Brian, myself and few other contributors here on the forum can help you, do your due diligence)  Investment property can be financed in an IRA, you must use non-recourse loan, there is a handful of lenders who specifically offer this kind of loans, here is a list that I compiled, hope you'll find it helpful:   https://www.biggerpockets.com/blogs/2810/50272-lis...Using leverage will result in UBIT on portion of the income of the IRA, not a deal breaker, but you must be aware of thisSelf-directed Solo 401k is exempt from UBIT on leveraged real estate, consider this option if you are eligible LLC inside of an IRA + Trust seems too complicated, keep things simple if possible 

I have made an offer to buy a duplex which was built in 1940s. During the inspection, the inspector pointed out the sagging of the top floor to us. Picture is linkedhttps://imgur.com/a/w5BhAXsAs you can see that it's ...

Not being able to turn on the power could be due to the property not having a main disconnect so the FSM could not check with a generator or a wiring/breaker issueI buy HUD homes for a living and my best advice is to only buy at a price that it still makes sense with the unknowns. 

I've been using the Farenheat portable electric baseboard heaters, but I think it is a bit too much for the current breakers.