Access to Cenrtral heating boiler for servicing inside a new kitchen i

I have a new kitchen installed by Homebase and a cupboard was put around the boiler. when I called a plumber in to service the boiler it proved impossible to access the boiler to service it. I was assured that it would be possible to access the boiler for servicing but this has proved impossible . It needs some parts of the cupboard to be removed to enable the boiler casing to be removed and the cupboard to be reinstated after the service. As Homebase no longer fit Kitchens they have accepted liability an d instructed me to obtain a quote to get the job done