Actually you've already broken from the recommended approach.
This is a project and every project should start with a plan and a bill of materials. Normally those are used to estimate project costs, track progress and identify potential issues.
You don't need blueprints, but at least a list of components is a good idea so you can get a second opinion.
The other year I got talked into assembling some bikes for a guy that wanted to build a couple bikes from the ground up. In spite of my reservations about his experience and lack of documented details, he insisted on going ahead anyway. Over the next 6 months I think we exchanged over 100 e-mails as I explained on an ongoing basis why the parts he was sporadically having delivered to the shop were incompatible with each other or simply wouldn't deliver the results he expected.
Eventually he did end up with a couple nice bikes, but the project took about 6 months longer than expected, cost him a small fortune, and he ended up with about $10,000 worth of spare parts that he had to sell off. Regardless of how good a price he got any of this stuff for - the overall cost was too way high. Some people claim a learning experience is worth something but there has to be limits.