These three letters spell two roots that look alike but split on the first letter. With שׂ (sin) the idea is paying for use: to rent, to hire, to earn a wage, שָׂכָר (pay), מַשְׂכֹּרֶת (salary), שָׂכִיר (a salaried worker), שָׂכוּר (rented). With שׁ (shin) the very same consonants turn to intoxication: לְשַׁכֵּר (to make drunk), שִׁכּוֹר (a drunkard). Modern Hebrew treats them as one written family with two threads. The wage thread is built from the pa'al / hif'il pair (you hire, you let out); the drink thread from the pi'el / hitpa'el pair (you intoxicate, you get drunk). Every word here is verified against pealim, niqqud included.
The same root runs through the verb system. Each binyan is a voice: it bends the one idea into active, passive, causative or reciprocal. Tap to hear.
Two clean contrasts live here. On the wage thread (שׂ), pa'al לִשְׂכֹּר is renting in (you take a flat) while hif'il לְהַשְׂכִּיר is the causative "renting out" (you make it available to a tenant). On the drink thread (שׁ), pi'el לְשַׁכֵּר is making someone else drunk, and hitpa'el לְהִשְׁתַּכֵּר is the reflexive getting-yourself-drunk. Same skeleton, opposite directions.
Same root letters, different noun moulds (mishkalim). The mould tells you the function: who does it, the act of doing it, or the thing produced.
Strip the prefixes, suffixes and vowels. Three consonants remain, and the meaning lives there.