Speaker cable length with monoblock amps?

May or may not be relevant to you but any cable less than 6’ is going to be a rough resell. Certainly if I was buying new that would be a major consideration. I use mono blocks that would work with a 4’ cable but I have an 8’ set and cross them behind the amps ie left amp is on the right side as I look at the speakers and so on

Someday you will replace your monoblocks with a stereo amp and your cables will have to be replaced. 
Alan

I had Kimber make me some 1' silver cables when I had a pair of mono amps. The idea that speaker cables have to be a certain minimum length strikes me as an audiophile myth; I've never read any EE theory supporting the idea. Real short cables can always be used as jumpers on speakers having two sets of binding posts (for bi-wiring).

What price levels of monoblocks and cables are we talking about? At high level you should not worry too much about resale value.

@inna $15k a set speaker cables and $22.5k a pair amps, your point being? Yes I could have them (SR) make me up a set of short cables for $10k but who wants to pay this much for jumpers? 

As another poster suggested one option to a “free” set of cables is to buy a 10’ set, have it cut and reterminated and sell the remaining 6’ as a clean set. AQ is a really good brand to do this with as they will change up any of their cables at cost (although personally I have never liked the AQ speaker cables)