What clone are you planning?
Don't get me wrong, I don't want your niches or anything at all.
But if it is one of the lower range clones, I'd STRONGLY recommend getting one developed from scratch. You can get a company to develop one for you for maybe $200 to $500 more, but proprietary code IS ALWAYS BETTER.
I have never owned a website clone myself, but I have definitely worked with clients in the past and I can only comment on the kind of hassle your developers will have to undergo in order to get your website up to speed. We spent hours upon hours getting rid of bugs and obsolete code - which was tormenting to say the least.
Considering the fact that they produce a plethora of clones, they're not able to actively develop a single product.
Most clone companies suffer from this. Active development is lacking and chances are you'll end up doing a lot of customizations.