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Thank you for the information and your question. As long as the tenant has a written lease that is still in effect and has not materially breached the lease, you would be bound by the terms. In other words, the lease follows the property and the fact that there are new owners doesn't change that. You might consider speaking to the current owners about your desires and ask, or require, that the home be free of the tenant for the sale to go through (may be too late for that but you can speak to your realtor about this). They may be able to offer the tenant "cash for keys." That is essentially like buying them out of their lease early. Or, you can offer to do so once you take legal possession. However, the tenant has no duty to accept the offer.
Please let me know if you need any clarification or have follow up questions.