Bill wrote ...
... in Arusha the rate we got was 1,200
Tz shillings per US dollar ...

Dave Patterson asks ...

I have clients arriving at JRO, going to Mountain Village for that
night, taking the 8AM flight to Kirawira. They will not have a chance
to exchange $$$ in Arusha. Did you note any of the exchange rates
at properties where you stayed?

It was either 1,000 or 1,100 at the lodges we stayed at (Serena and
Sopa) ... but everything at the lodges and National Parks from cost of
drinks to Park entry fees is also quoted in US dollars so they could
get by without changing any money, most likely. We exchanged some
because we were going to a market in Arusha to buy extra bottled water,
bags of rice for camera support bags, sodas and a couple of other items
but otherwise we could have paid everything else in $$.

Bill