Own contribution - how to present it to the financer?

With all due love for this self-performance calculation, I must point out that very quickly a lack of motivation can arise, possibly one gets sick, and besides material, tools are also needed. In my opinion, often a simplistic calculation is made way too quickly. To be honest, one reaches psychological and physical limits very quickly that were not considered beforehand. I definitely don't want to discourage anyone, and for some everything goes well, but I want to encourage considering this as well.

Regards Sigi