Hi. Been attending the numerous electronic fairs in Asia for the past ~20 years in HK. They are a must visit and should be on your list of things to do, after this covid nightmare slows down. Pending a clean slate, hope to visit the fair this October but the dates are not yet announced so it may be virtual again.
In the past, have absolutely seen firms with pre-built modules for use in furniture. Looked like a massive Staples office store with clean tables with assorted mounted power widgets.
You can start with this vendor:
https://xjynew-epoch.manufacturer.globalsources.com/homepage_6008851511454.htmDo review their # of years in the business. If they sell toys along with these goods, I would give them a pass. Have seen some that will just be 'traders' and flip anything for a dollar. It is the way of the east. If it is popular, sell it today and next week it will be something else.
You only want to deal with the manufacturers.
You can, at your expense (which is not much and ~200 USD / day) - perform an onsite audit from ISO certified inspectors. They will act as your agent and inspect the company; visit them; supply you with an audit report for your review. Global Sources along with others offer such services.
Many / most of these companies are real. They want your business while others are looking for the next 'Apple'. This week, we were frowned upon on our forecast of 10k-50k pc buy of AMOLED displays - seriously
Been in the business for ~40 years and the vendor is being selective on who to sell to when just about everyone has these displays ? Found 3 backup vendors (real mfrs) we can use for our pending designs.
It is a large field of suppliers for just about anything you can dream of. Start with the above and consider Global Sources and/or Alibaba to broadcast out a RFQ. Your emailbox will be flooded but then you can weed through to find a proper business partner.
DO NOT prepay for large volumes of anything. Paying for samples and shipping is normal practice. Do consider to buy with escrow services if there is that option. Alibaba has a link to the vendor reviews and $$ of sales to date, they cannot fudge those values.
Be sure that the modules you select are able to meet your requirements and they can back up their claims.
Good luck.