If your lawyer is your confidant, you might consider having the first meeting at his office, but many of these exploratory meetings are fruitless, and it will be expensive if the lawyer is in at the outset for each suitor. And the atmosphere of a lawyer's office is not conducive to quick rapport. Buyers like to meet the management team, not just the owner. Don't introduce buyers to your key employees until you feel confident that a deal is likely to be made. Visitors should be qualified in advance.
Many buyers plan to use other people's money.
Don't be reticent. Ask about the funding. Ask how much equity the buyers would invest, and how much they plan to borrow. Ask about other transactions this buyer has concluded. Learn how prior acquisitions were financed.