That's the problem with trying to flip inexpensive bikes. There is no room in the price to sell at a profit after you pour a boatload of money into it (paying somebody else to fix it and slapping on new parts).
You need to stop the bleeding. Look for inexpensive original type used parts on CraigsList, at the local Coop, in the LBS bargain bin, or on eBay. Don't buy new, modern parts for the bike, they will not increase the value of the bike over the value of the bike if you find some nice used original type parts. In fact new modern parts may actually hurt the selling value of the bike.
Learn to fix it yourself. The profit in a flip bike comes when you buy right, and fix it yourself adding inexpensive parts from your parts stash. If you are going to pay someone else to fix a flip bike, you might as well let them bike the bike instead of you, and they can take the final risk, not you, because you will not make a profit.
At this point resign yourself to riding the bike or breaking even when you sell it. You won't make a profit by the time you buy the parts you still need. There is a limit to what you can ask for this particular bike, if you expect to sell it this year ($150-$175, after completing fixup, if you are lucky and you are willing to wait).