Fiesta 1.25 judder (misfire)

Hi, 

I’m new to the forum and hope you can help me resolve a judder I’m getting from my wife’s 09plate fiesta 1.25.

so there’s quite a back story so bare with me. 

We brought it a month ago on a Saturday and drove it home. the next day we took it for a 80mile joinery, but half way it broke down.

diagnosis by the green flag man catastrophic overheating and signs of milky contamination to the engine. Back to the garage, they replaced the cam two valves water reservoir and leads.

i wasn’t able to obtain the receipt as the garage were becoming difficult to deal with.

after two days the car then developed a misfire so we took it to a main ford dealer (having lost all confidence in the other garage) and they diagnosed a split lead which we had replaced along with the plugs as it was Advised due to the poor condition of the existing ones.

finaly after the repair I noticed there was a oil leak about the size of a dinner plate accumulated overnight while parked.

so back to the garage, water pump! 

My wife had hoped this would fix the  judder but it obviously hasn’t. So she told me about this judder still happening as I don’t tend to drive it.

 It occurs low revs, And I’m guessing it to do with the original repair not being done to a good standard!  I’m really not a mechanic but Do you think the head didn’t get skimmed and is messing with the compression or I have read about coil pack? 

I really could do with some advice and maybe recommendations for garages who really know there trade.

my wife has said to sell but we would loose A lot of money so  while it may cost a few ££ I’m guessing it the most economical option.