Go thru (create) fair commercial property lease

I am going to lease commercial property (small shop). As I am new to renting of commercial property in UK (Scotland actually), I need some legal advice:

- what is "usual" to have in lease
- what is unusual
- what will happens if something will go wrong (break clauses etc.)
- insurance, reviews...

The final should be balanced rental agreement I will understand and in will be acceptable by both sides.

I have already got draft lease from potential landlord in which I do not understand some parts of and some parts seems to be too in favour of landlord... So we could work with it.