Family of 7 (one too many, ugh)

[ClayJar11]

Ok here is my deal. We are planning on a 12 day disney vacation for May in 2014. I am well aware that thats over a year away , and prices won't be out until May/June. To find a ballpark price for us i looked at similar dates for 2013. For a room to accomidate my family of 7 for only 7 days, let alone 12, (with meal plan) was over 9,000$. I cant seem to justify the cost though. I know all of the perks of staying at Disney, but for a good vacation home for 12 days (3 miles from disney) , it would be roughly 3500$. Add 7 day disney passes (we dont intend do use park hopper), thats around $1700. So that brings my total to $5200. So thats a differance of $3800. For a family on a budget (tho somewhat flexible), Im just not seeing how staying on Disney property works for us. 3800$ more to stay on property ?(the difference of the cost with meal plan vs without semmed minimal)? Now i know alot of this has to do with the size of the family, but does anyone have any thoughts or tips on this?