I thought I'd start an new thread since existing threads on this topic are old.
I did read previous threads and found several people recommending Rose Pest Solutions. (I also read recommendations to avoid Ace and Redwine.)
So ... I called them - Rose Pest Solutions 513-481-9630. Got a very pleasant and careful man, Paul Stacy. I appreciate him for being honest and saying I had too much clutter for a professional to really treat the place. Priority is getting rid of the clutter.
Now that it's summer and HOT around here, he said it would work to put stuff in a closed black trash bag in the sun to heat up. Just one day would do it, he said.
He also approved my idea of covering the mattress, springs and pillow cases (I already ordered Hospitology Sleep Defense covers).
And approved my idea of puffing silicone dust between the mattress and springs (I already ordered CimeXa Insecticide Dust from Amazon). He said go easy with it, though - just a puff, once every three weeks.
Also approved my plan of putting Bed Bug Traps under the beds and sofa legs (also already ordered from Amazon).
THE BEST NEWS: he thinks it's possible that I only had the one bedbug!! Okay, I find this highly unlikely, to be honest. But I do hope that it's only a few!! And that the silicone dust between mattress and springs will dispatch with them.