Connect central locking issues

I have a 2010 T230 Connect and this year I have had endless issues with central locking. One time I was unable to access the back of the van for 6 weeks, various 'expert mates' prodded about to no avail. I could only access the cab using the door key. One day I bought 2 new fobs from Amazon, the advert showed genuine Ford fobs only to find when I received them they were copies. However I tried setting them up, one worked the other went straight in the bin as it was crap and I was able to access the back of my van again. 

Now the same thing has happened again about 4 months later. Been playing up for about 2 weeks, but to get in back of van I pressed the centre button on fob and doors unlocked. Now only front passenger door works with fob, drivers door has to be opened or locked with key in door lock and I cannot access back. Even the inside side door release (reach through cab cage) won't work. I keep the side door contacts clean incidentally. I have put new batteries in fob, checked batteries and the fob connection terminals, 3.25v.

I enquired for a new set of keys incorporating the fob in the key and was quoted almost £300 from a car lock dealer. Even then they won't be genuine. 

A Ford garage guessed it will be a processor issue and estimated approx. £900 + vat with out looking at it, or £150 + vat to investigate and give me a quote. 

At the end of my tether with this van now, thinking of scrapping it and buying brand new. Its cost me almost £2000 these last few months in various bits and other work. 

Anybody got any ideas????