One　of　the　many　barriers　to　decarbonization　and　decentralization　of　the　energy　sector　in　developing　countries　is　the　economic　uncertainty.　As　such,　this　study　scrutinizes　economics　of　three　grid-independent　hybrid　renewable-based　systems　proposed　to　co-generate　electricity　and　heat　for　a　small-scale　load.　Accordingly,　the　under-study　systems　are　simulated　and　optimized　with　the　aid　of　HOMER　Pro　software.　Here,　a　20-year　average　value　of　discount　and　inflation　rates　is　deemed　a　benchmark　case.　The　techno-economic-environmental　and　reliability　results　suggest　a　standalone　solar/wind/electrolyzer/hydrogen-based　fuel　cell　integrated　with　a　hydrogen-based　boiler　system　is　the　best　alternative.　Moreover,　to　ascertain　the　impact　of　economic　uncertainty　on　optimal　unit　sizing　of　the　nominated　model,　the　fluctuations　of　the　nominal　discount　rate　and　inflation,　respectively,　constitute　within　the　range　of　15-20%　and　10-26%.　The　findings　of　economic　uncertainty　analysis　imply　that　total　net　present　cost　(TNPC)　fluctuates　around　the　benchmark　value　symmetrically　between　$478,704　and　$814,905.　Levelized　energy　cost　varies　from　an　amount　69%　less　than　the　benchmark　value　up　to　two-fold　of　that.　Furthermore,　photovoltaic　(PV)　optimal　size　starts　from　a　value　23%　less　than　the　benchmark　case　and　rises　up　to　55%　more.　The　corresponding　figures　for　wind　turbine　(WT)　are,　respectively,　21%　and　29%.　Eventually,　several　practical　policies　are　introduced　to　cope　with　economic　uncertainty.