SEAI one stop shop / use existing contractor

Cards on table, I have been doing independent heat loss surveys successfully for nearly 2 decades now. In my world, it is vital to know what is at issue first before embarking on expensive works. In the majority of cases, the main issues do not necessarily need to cost a kings ransom to sort out. The BER system of rating is not up to scratch to do this. My advice is to be very beware of OSS's and their promises.
 
What is OSS's ?
 
Completely agree, we did the initial survey via an OSS and it was a really negative experience. Their staff did not understand the end to end solution of what they were talking about, one guy was obsessed with windows, another with heat pumps. Ended up going with local providers for external wrap, solar and heating controls, working out around 10k cheaper then the OSS and just required a little project and contractor management from ourselves.