Replace old fescue lawn
My original fescue lawn (appr. 2000 sq.ft) was once replaced because of bermuda invasion. The grass was killed with round-up (unfortunately there is no barrier between the lawn and my flower beds, much of the flowers were harmed, many killed). , then the "grass" was removed and new sod was placed. Now bermuda came up much faster and in a few years the lawn is shot. Apparently, the bermuda rhizomes were too deep and also infiltrated the flower beds and came back to the lawn, also the once a week gardener brings in much infestation with his mover.
One neighbor replaced his lawn with plastic, I don't like plastic and also it is very expensive.
What should I do, please advise. Thank you.