"Would" and "Will" are both auxiliary modal verbs.
..our store's technicians will fix it free of charge. (=The technicians will fix it free of charge) (surely they will.) (strong probability) (unavoidable)
..our store's technicians would fix it free of charge. (=The technicians will fix it free of charge) but (not strong probability)
We use "Will" to talk about: promises, offers, facts about ability or capacity, habitual behaviour, (for the events that are unavoidable) (definite future)
We use "Would" to talk about: invitations, hope, desire, requests, asking permission, to indicate the consequence of an imagined event or situation. etc.
Would you like to join us? (invitation)
I would like to have a cup of tea. (desire)
(We use "Would" as the past tense of "Will" too but the question is related to the future)
(Note: The question is about "Will" and "Would" and not about "Should". ("should there be any problems with your new computer" means "if you have any problems with your computer")