First thing you’d need to check before you agree to anything is that your house will get a Band D rating needed to get the FIT tariff at the higher level.
That can be difficult sometimes for houses heated by electric.
The software used to produce Energy Certificates (rdSAP) hates electric as a means of heating a home as it’s the most expensive way.
I installed one last week in Carluke off the gas grid with a wet electric heating system rating before solar was and F. To get to Band D she had to top up her loft insulation, fully install LED bulbs and fill her gable wall cavity and install solar. After all this had been done, she only just got to a Band D.
Luckily I was able to get her a Green Homes Cashback grant to cover the costs.