Ye Gods, YouTube channels on keyboards must be truly terrible if they are seriously suggesting group buys as a way to save money in this hobby.
They are a way to get very low production enthusiast kits, but they are by no means 'cheap' and there are very probably risks of long delays or total non-delivery. Spend some time in the group buy forum to get a feel for how these things proceed before getting involved.
Want something simple and hot swappable to try things out? Look at GMMK.