Thanks for the preliminary info.
Based on my previous ROI estimation of 2 years your bulb will be charge every 2 years at 720THB.
I will study more your offer.
On down side, after 2 years we have pay for the light bulb but we will keep paying after 2 years
On the positive side, you warranty the LUX level + my finance department might have another interest as no more CAPEX…