IMHO, there are some jobs where the $ saved is not worth the time, effort, cost -> i believe the most expensive part of a roofing contractor's fee is the dump fee for the old roof -> potential risks -> the aforementioned flat tires - > heat-related issues -> fall-related issues -> and then you have to be perfect with nail placement or the roof will fail. and do you want the new owner to come looking for you after the property is sold?
sure, you can say 'i re-did my roof', but at what cost? what did you really save?
at a minimum, buy the shovels and a large magnet bar for the nails that fell to earth. even the pros miss 'em.
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“Everyone should have a horse. It is a great way to store meat without refrigeration. Just don’t ever get on one.”
- ponder's dad