When preparing for the inevitable costs, always make sur you know the age/condition of your big ticket items.Roof, plumbing, windows, electrical, HVAC, foundation 

Heating/AC, appliances, electrical, windows, paint, etc. 

How is the electrical, plumbing, roof, HVAC?

Guests, just like those at your personal residence, require all sorts of amenities we don't often think of beyond the heating, cooling, water, waste, electricity and internet that hosts are responsible for.

He bought a 4.5KW electric radiant heater with windows open at night. 

Are they showing you the roof, electric panel, crawl space?

Walls Remove/treatmildew (per surface) $15.00 Repairholeinwall $55.00 Repaint(perwall/ceiling) $30.00 Doors Replacedoor(inside) $165.00 Replacedoor(outside) $485.00 Electrical Replacelightbulb $3.00 Replacelightfixtureglobe $20.00 Replacelightfixture $65.00 Replaceelectricaloutlet/switch $15.00 Replaceelectricalcoverplate $2.00 Plumbing Replacekitchenfaucet $150.00 Replacebathroomfaucet $105.00 Replacefaucethandle $20.00 Replacefaucetaerator $10.50 Replaceshowerhead $27.00 Replacetoilet $175.00 Replace toilet seat $25.00 Locks Replacekey(doorormailbox) $10.00 Replacecylindricaldoorlock $35.00 Replacedeadboltlock $25.00 WindowsandWindowCoverings Replacewindowpane(sgl) $75.00 Replacewindowpane(dbl) $125.00 Replaceminiblind $20.00 Rescreenwindowscreen $25.00 Replace window screen and frame $50.00 Miscellaneous Replacerefrigeratorshelf $25.00 Replacestove/ovenknob $20.00 Replaceplasticcountertop $275.00 Replacemirror $45.00 Replacemedicinecabinet $75.00 Replacetowelbar $25.00 Replaceshowercurtainrod $25.00 Replace shower curtain & rings $13.00 Replaceshower/tubenclosure $350.00 Replacethermostat $80.00 Replacefireextinguisher $30.00 Removejunkanddebris (per area) $35.00 Replacesmokedetector $15.00 Replacecombodetector/alarm $40.00 Replace alarm battery(perbattery) $2.00 Replace drop ceiling tile $10.00 Replace wireless doorbell $35.00 Actual charges may vary based on condition and/or vendor bill.

In November 2018, I purchased a $63,000 ruined house on the South Side of Chicago, in an African-American neighborhood, and started renovating it, both with my own hands and with outside experts in plumbing, electrical, etc.

Is there electricity there?

But, if there’s a roof, bad plumbing, electric, water damage mold, if there’s multiple BIG issues, it’s a no go as it will not be cheap.