If you have no intention on listing the house instead of wasting an agents time with a fake listing appointment you could hire a realtor to do a BPO (Broker Price Opinion) which should only cost about $50 and should provide you with enough information to see if the appraiser was way off.

Finding a partner or mentor can cost money on your first few deals, hiring a guru costs money out of pocket. 

(my bf can do most construction type work, but there are situations where he may not be available so I'd have to do it myself or hire someone?

I'm a freelance video editor, but grew up working as carpenter for 7 years before going to film school.

It's highly dependent on who you hire I have discovered, I have rehabbed  with 'side-job' workers for a fraction of the price.

Can you hire a part time person to work in the cleaning business while you establish the 2 years of income?

You may want to consider hiring a good architect  and contractor with experience with this type of work. 

Hiring a contractor is also a good idea, however your inspector (if they are good) can give you rough estimates or tell you directly if its something to walk away from.  

Then use that to hire another corporate property manager.

Cheaper than hiring a lawyer and cheaper than most of the other gurus out there.