These are a few tips applied from great companies in other branches.
They will fit to you business model as well. It will require some adaptations
Lesson 1: sell the main product cheap. Make it a must to have expensive accessories for it. The product is just a naked frame where other expensive parts should be added.
Never tried to buy a flight ticket with Ryanair? Put a lot of add-ons in the selling process when the customer is on the to the check-out.
Lesson 2: make the check out a complex process made of many steps. You will have the opportunity to add new sells at each step.
The department stores has cheap alluring items at the end of the store in the area between storage and payment.
Lesson 3: add cheap alluring items at the very last sell process step
Traveling back to Ikea store to change items with low quality? Buyers can change bought items at their will. It will cost the money for a travel to the IKEA store(fuel, car maintenance) but they do not think about this. Clients are given the opportunity to fill an IKEA cash bonus card when returning items back. This card can be used to buy goods at the IKEA store only.
Lesson 4 A: Use bad quality to increase sells. Never heard of scrap-ware?
Lesson 4 B: put the burden of quality control on your clients. Make the clients do the quality control work.
Supporting external software or products.
An example: AWS, however, sees the partnership from a markedly different perspective. In the AWS worldview, supporting VMware software in its cloud is just one more way of helping companies go all in with AWS, since it gives them the ability to use familiar tooling while on the road to migrating all their tech to AWS.