As so happens from time to time something breaks in your business and you realise just how vulnerable you are. When we analyse our business its about 50% retaining walls/hardscaping and 50% straight up machine works. In reality its often a mix on most jobs. If you take the devil's advocate view and look at your gear; what are the (old military training) mission critical items??...the things that if they bust you are up the proverbial creek with no paddle. In general terms looking at our business and excluding the machines themselves because its hard to plan for redundancy in that regard: the first item...at the top of the list and the most critical is our 9 tonne (20'000lb payload) Mitsubishi dump truck. It hauls the machines and various trailers. It brings the materials and hauls away the waste. Without it we are almost totally screwed. Next on the list is our David White laser - back up plan is to hire one but we already could use another so an additional laser is into the plan. Then there is the Husky 16" saw - can hire one but we could get by with a smaller lighter 14" and it would be a good backup. and so on. In the main we can get by...the Excavator can do some work of the skid work and vice versa if required. We have maintence plans and equipment renewal plans to address this things as much as possible. For example we put aside money for track and tyre replacement on the Ex and the skid. The rockbreaker annual service is built into our budget and so forth. When it comes down to it how well will your business fair??..do you have some piece of equipment which is pivotal to your business. The truck thing is scarey for us.