random sampling of all possible combinations

Hi

I am investigating the combination of vehicles and houses. House 1 can have one or two vehicles, House 2 can only have one.

I have created cells (VID1 and VID2) that contains all possible combination of vehicle(s) a house can have. Now I combine the houhses like this

i=nchoosek(1:numel(VID1),2); %all possible combinations

Now when I am testing I only have three vehicles, but later I will have up to 429 vehicles and 36 households. So I need to limit this function somehow.

e.g. if I have 100 vehicles then this would be

i=nchoosek(1:10000,2)

How do I limit the number of combinations and how can I decide how many combinations is reasonable?