The house I have been renting for one year now is in El Batey, in a very nice neighbourhood. The landlord is from Santo Domingo and he never increased the rent. I guess he just wanted someone to be there and take care of the house.
The inverter is pretty big (8 batteries) but only works with 4 right now. But we never have problems with it, it can last for 7-8 hours, sometimes more. And here in Sosua, we get 2-3 hours electricity, sometimes more, everyday. It is enough to recharge. But also, there is no one in the house during the day.
I know I will not find another opportunity like that, but maybe someone who rents his place cheaper because they need someone to take care of it...