I have heard of people and know people successfully running Long Esters in a 6 week period, but the dosages are generally very high and they are usually very advanced. The average person , from what I have learned, usually should steer away from this kind of thing and settle more for short esters in a feasible quantity.
I guess the first thing to ask is what your goals are of the cycle, and what you plan to get out of it? If you're trying to get the kind of gains an IFBB Bodybuilder is seeking in a 6 week cycle, then you're probably looking at running quite a few grams.
I think I posted a while back about this, but a particular buddy of mine that got his IFBB Bodybuilder pro card comes to mind. He was literally tapering down from almost 3,000grams of Deca down to the 2K marker , and this was alongside very high test, 300 anadrol/250 anadrol/200 anadrol a day as the weeks tapered down,etc.
We're talking 2K/week of orals alone on Week1....but his cycles were indeed very short, that's how he has to do it though.
If you're a mere mortal and not looking to be an ifbb bodybuilder, I can only speculate that if you cut these kind of doses in 1/2, the results would be pleasing enough,but in that case, you may as well just run the darn short esters because you'll pretty much be injecting the same oil anyways?
For example, a decent short cycle would be a Test Base of 1K+ (you can find 400ml concentration and even 500ml from a few sources...that's only 2-2.5CC right there), and then add 1000 NPP a week alongside orals(100 anadrol a day,50 dbol or something like that) for 6 weeks if you are really stuck on 6 weeks. If you are a tren user, then the oil volume goes down even less because 1K tren would be ridiculous(not saying that 1K NPP isn't already pretty high...but you get my point).
10 CC + 2.5CC = 12.5 CC ; you could just do 4 jabs on Mon-Wed-Fri-Sat...
3.1CC in each jab and have site rotation of big muscles that hold that much without problem ( Left Ventral Glute/Right Ventral Glute/Left Dorsal Glute/Right Dorsal Glute/Left Quadricep/Right Quadricep/Left Chest/Right Chest....that's 8 sites right there so you can hit a site every 2 weeks).
PS, I know it is a factor, and I do understand it....but I really hope you're not basing your cycles just on how often you have to insert a needle in yourself; most people would say "this isn't the right hobby or sport for you" if that's the case. The cost thing, I can understand more, but tbh if you have a good source, all these compounds nowadays are extremely cheap..... It's only GH/Insulin/Pharmacy Primo/Anavar and Primo(kind of) and other stuff like that which really cost quite a bit. Test is DIRT cheap. NPP is DIRT cheap (I seen sources for $17-18 for 1000mg vial...100% legit sources). Tren is pretty freaking cheap considering how little you need for pronounced results.
Just some things to think about......