I also live east of Dallas. Not much in the area, Dallas is too metropolitan for RV parks. I think Roy and Sally, olcoon on the forum, have stayed at a COE park near Lake Lavon, which is NE of Garland.
Sandy Lake and Grapevine are not "near" Richardson/Garland and due to construction would be a very "un fun" commute. There is a park in Sunnyvale, which is slightly east of Mesquite, which might be closer, but I have not stayed there, only driven by.
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