They complained of the oven and crumbs under a heavy sleeper sofa they moved when the moved in some of their furniture.

I have 3 young children and need to focus on family and I don't need a second full time job. 

That's how you get the best of both worlds.I will defer to your judgement / answers as you are going to be more of an expert in the area and I am just basing it on spending a few months there and potentially wanting to live there in the future.Maybe I chose a wrong word when I said 'poor'.I stayed in Madrid during my time and I just based my response based on discussions I had with locals and 'high level research' on the internetIt appears that unemployment rate is high in Spain at around 11 percent with a higher rate for those who are younger.A had discussions with many where they are mentioning to go outside of Spain if they want to further their career or get a higher salary.locals have told me that it is difficult to start a business in Spain from getting approval and the taxes are higher for those that are self-employed.My personal assessment, which I think agrees with yours, it will be hard to make a rental work if you target it to locals but if you target it to outsiders, you can make it work.During my stay in Madrid - I stayed in Chamberi, Lavapies, La Latina, Malasana and spend around $60 to $120 a night mostly in airbnb's(basic rooms with basic furniture). 

I suspected that 1st floor condos don't get too much love, but since this condo doesn't have an elevator, I figured it would be easier to move furniture into.  

My father recently passed away with all of his assets in trust to to be divided equally between his three children.   

A lot of people have problems seeing how the space would look with furniture or even what some rooms are. 

Housing stability is important, especially to families with school-aged children.

Water is easy - bill divided by total occupants at property (count everyone even children) then for each unit multiply the result by the number of people living there.

However, it needs a good $100-150k in repairs/updates, which may be significantly higher due to specialty construction.Since the grandparents passed away, the children are thinking about selling. 

I recommend looking into areas near economic bases - close to Nationwide Children’s Hospital, Ohio State Campus, New Albany, etc.