BMII Issues and Advice Required (Please)

Hi, I've got one of the typical Suprima 40 and BMII installs.  The boiler and BMII are 17 years old now and haven't (in the last 5 years) really been looked after.  The Suprima needs a new PCB due to cut outs and needing to be often reset. The BMII is giving a loud buzz every day or so for a few seconds, likely requiring a new PCB also.  To make matters worse, the top tank appears to have a small leak (see first image) and there is a fair amount of corrosion on the bottom (see second image).

The property is being sold soon, so want to keep the cost a low as possible, but get it working and presentable.  Can the issues in the images be repaired?  Would I be correct is saying that the easiest and quickest and likely cheapest option is to replace the boiler with a cheap combi and remove the tank? ...or would a like for like replacement be cheaper and/or easier?  Any help or advice would be welcomed.  Thank you.

The top tank could be removed and a plastic one fitted.
The plastic one could be put on shelf brackets and ply
Or battens & ply.
Cold feed and overflow would need altering / connecting
Same for unit cold feed & vent.

But it does seem you have an issue around the immersion heater and drain off.

The buzzing noise will be PCB but check if water from the top has travelled down

The you have the Potterton issue too.

A new combi would be nice
Or reduce your selling price

Mike

Thanks for the information and taking the time to reply! Cheers!