My Boss offered me a chance to take over the business I've worked at for 10 years. Where do I even start?

I've worked at the same small auto repair shop for almost 10 years. I started doing basic work and eventually became the person who handles a lot of the daily operations.

The owner is getting older and recently told me he's thinking about selling. I asked if he would ever consider selling the business to me, and to my surprise, he said yes and offered to help me learn the parts of the business I don't already know.

The shop has been around for over 20 years, has regular customers, several employees, and a good reputation locally. I know how the business works day to day, but I've never bought or owned a company before.

I don't have enough cash to buy it outright, so financing would probably be necessary.

What should I do before even discussing a price? Should I ask to see several years of tax returns, profit and loss statements, debts, equipment values, and the lease first?

I'm also wondering whether I should form an LLC before buying it, and whether buying the business assets would make more sense than buying the existing company itself.

For anyone who has bought the business they used to work for, what do you wish you had checked before signing anything?