I agreed to john-pero. Ask your client to explore trial license of Pro 2020
They may purchase the license directly to Intuit for $300 (i.e 1 user) or thru a partner for around $200 or less. To convert their data from QBO, utilize a free converter tool (for now)
And for yourself, consider to have a QBD 2020 Premier Accountant edition. If you are not a ProAdvisor yet, consider purchasing a one-time license thru a partner, Company only offers the subscription one.