think the gearbox has gone? I have a 99 V reg Mercedes A Class that has done 70,000+ miles, whilst driving it the other day I could not get it into 1st or 3rd gear. After reading on what car that the gearboxs do fail on these cars I am assumming I need a new gearbox? I could still use 2nd,4th and reverse. Having just gone on maternity leave and also I am wanting to sell this car asap,I am looking at the cheapest, easiest way around this? Any ideas would be greatly appreciated.

has the oil in the box been checked it may be low which would cause that problem to sell it in that condition you will have to sell it cheaper than the normal going price there will still be alot of interest as you have a good make and they don't depreciate like a ford

You dont say if yours is manual or auto or semi auto, if manual which it sounds like it is the the plastic linkage needs replacing, not expensive and easy to do.
jib