how many night nappies?

We only have 2 dedicated night nappies atm, with 2 more on order (one should be arriving in the next couple of days). I want to get at least one or two more as I like to have 5 or 6. But I think I need to sell another of the ones I have currently, as it just isn't up to the job.

I will probably buy some more of the ones I have on order, depending on how well they work.

We've been heavily boosting some day nappies to get us through (I have to heavily boost the 2 night nappies we currently have too )

I only have 4 at the moment which is simply not enough with 2 babes in cloth! Ideally I would like 8 to allow for drying time and a bit of variety
I am making do with heavily stuffing our day nappies but it's not really foolproof!
Keeping my eyes on the classifieds

ok think I'd like 5/6 so that I can wash every 3 days, will have to go count how many I have, less than that I hope