Commercial landlord tenant law regarding security deposit in MD

No, That kind of treatment needs to be addressed in your lease. Hopefully, you have not signed it yet and therefore can request what you want. Most likely the LL will not agree to pay you interest, but they should agree to maintain the money in an escrow account. Since a commercial lease is probably one of your largest expenses in running the biz, it would be best to let an experienced commercial real estate attorney review the lease to see what else needs to be changed. Good luck.

Commercial leases are a bit different then residential leases. In either case, the lease will most likely have the answer/authority. You need to have an attorney draft the commercial lease, therefore your interests will be protected.

No. Commercial leases are the wild, Wild West of contract negotiation. Whatever you agree to is your deal. If it says nothing about escrow or interest, the landlord can keep the money in any reasonable manner, even in a general fund.