Are small tools fixed assets or expenses? I purchased a blade that cost $70. These tools I need for machines to run production.

most of the time is a different tool. It could be industrial needles or different parts for machines, and costs vary from $5.00 - $200 

I have an account set up as: 

Expense - Repairs and Maintenance

It is different but it might fall under the same account category. If I build an extra room inside my warehouse, I purchased all the materials, and to me sounds like it could be an expense although a fixed asset because in the end it became a small room/building.

• wall & roof sheathing.
• Framing materials.
• Fasteners.
• Interior and exterior finishing materials.
• Plumbing materials and fixtures.
• Materials for the electrical system.
• Windows and doors.

And if we paid a licensed electrician and plumber to do couple job in the warehouse would the transaction be recorded as 

contract labor - expense

or Expense - Repair and maintenance?. 

Thank you in advance.