Whereabouts are you located - UK, Europe (typically western) or USA/Canada - or somewhere else "far away"
Presumably there is power in the garage (as you refer to using assorted kit there)… If you're in the UK/Europe… then options that don't require actual physical cabling are available - and not using a wifi repeater either.
Check this post for the discussions here that include the use of LAN over mains adapters:
This LAN over mains option will apply easily in UK, likely so in Europe too. In Canada/USA likely so as well - but you would need to check what kit is actually available there - as Devolo isn't. Note the latest Devolo kit also includes extending wifi options too...
message edited by trvlr