Yes, this seems like a pretty good deal if the property is already remodeled and ready to rent out. Can you rent the studio to someone separate? That could be a cash cow.
You won't be able to pull the $42k out though. Unless you find someone who will do a 95% LTV investor property loan, you should plan to leave 20% equity in the deal. If the house is worth $122k, 80% is $97k. That is the amount you could expect to go to the bank for. BUT, you probably wouldn't get it until it's all been seasoned for 6 months.
Up front, you could purchase it via an FHA loan with 3.5% down but you'd have to move in.
The easiest way to do it zero down is if your grandma owner financed but if the title transfers that could trigger the due on sale clause.
Is she willing to lease option it to you? That way you could get control of the property and could build some equity in it for some period of time. By the time you need to exercise the option, hopefully you're in better shape. Maybe save all the excess rent you are collecting to use as a down.
I'm sure there are some even more creative ways to approach this.