PeteH My recommendation would be try to undertake it yourself. £140 plus parts, means dropping £160 on it, perhaps delivery and vat costs too? On a 3 year old bean to cup (BTC), you may get future problems. If it again costs a similar amount for a small job, you will soon have purchased almost 70% of a new machine.
Now I know you probably purchased a bean to cup for the sheer convenience, and when I cared for my my mum here, she could use a BTC machine even with the dementia, which wasn’t very advanced then. However, it might also be time to consider stepping up to semi automated machines and a grinder. They will make much better coffee, steam milk much better and are not that much effort to use. Definitely worth checking out the classifieds.