maybe 1 maybe 0,maybe 100
its a numbers game in order to get a decent average, if you hit a good area you will get a good return , bad areas where there is window cleaner saturation you wont get much so you probably wanna try drop a 1000 a week, or in lumps of 5000 + to get a decent return,
so if you get nothing from the 1000 dont think leaflets are no good, just keep at it, also the design might be able to be tweaked to improve your success a little bit
also door knocking if you are desperate for the work will multiply your success rate immeasurably but it is more time consuming and some dont like it
good luck