Any Positive One Stop Shop Stories?

We just had the Home Energy Assessment completed today, and we're inquiring at the moment about our options.

I’m feeling optimistic, but I suspect the quote will come back quite high. Unless it’s a complete no-brainer, we’re planning to compare costs by breaking the process down and doing it step-by-step through individual grants.

I’m curious about others' experiences with One Stop Shops. I’ve seen plenty of negative reviews—are there any positive ones out there?

We’re in a 1950s home and looking to get the place fully insulated so we can install a Heat Pump. Once the insulation work is done, we plan to do an airtightness test to ensure the Heat Pump will be efficient and not cost an arm and a leg to run.

Any feedback on retrofitted Heat Pumps would also be much appreciated!