One is mechanical / general so it can cover most anything.

Or are you talking about unit walk throughs, checking roofs, foundation, plumbing, mechanicals, lease audits, etc?

The mechanic's lien is created by operation of law when the services or materials are provided.

They then put a Mechanical Lien on your property if you don't pay up and try to push you into foreclosure to try to get the property from you. 

There's a lot of discussion around partnerships, private lending, and hard money, but I don't see much discussion on the actual mechanics - what these arrangements look like in practice.My hope is this post can serve as a reference for those starting out, so we may get a better understanding of how these strategies are actually implemented as well as an ability to more accurately predict the profits and returns you and your lenders and partners can expect.If those with more experience would like to revise these numbers and statements, it would be most appreciated.These scenarios assume you, the flipper, are bringing none of your own capital to the deal.Typically, this would mean 1 of 2 scenarios...Private Lending - Someone you know brings 100% of project costs (purchase, rehab, acquisition costs, holding costs) to complete the deal and in return, they get a certain percentage return which comes out of your profit.Hard Money + Partnership - You get a hard money lender to cover 80-90% of purchase+rehab and a partner to cover the remaining 10-20% as well as acquisition costs (including hard money origination and points) and holding costs (including hard money interest payments).An aside about the structuring...Private Lending - A promissory note is created, and your private lender lends to you or your business. 

On a composition shingle roof, you would have a flashing that is integrated into your shingles (like the roof vents you have now) below the flashing (or integrated into the flashing) is a mechanical base that connects to the structural members of your home (rafters) or the deck (plywood), dependent on the racking manufacturer.

Systems are mechanical and they can break.

lots of work in NPN.. and there are good performing notes but you have to know how to vette them. the mechanics of the transaction is not that hard.. its figuring out what your buying that is the trick

I'm a Mechanical Engineer studying to get an MS in Aerospace Engineering. 

Specifically general mechanic that is jack of all trades, an electrician, plumber,and a roofer!