Graham, I already had a an early 60's Rollei but decided to start again with an early 70's Yashicamat 124. I was given the Rollei many years ago because although mint it didn't function properly through lack of use since new.
One thing you have to watch is the shutters on any of these TLR's a CLA (clean, lubricate & re-assembly0 will cost around £50 in the UK.
I bought a reasonable Yashica, but the slow speeds were sticky & I had to pay the extra £50 to have it serviced, I had the Rollei serviced at the same time.
If you buy a Yashica don't pay too much, make sure it has a Yashinon taking lens, the LM's, 124 & 124g are the best models.
Sometimes Rolleiflex's can be found at reasonable prices, MWClassic's had one for £99 but it's better to pay more and get a decent robust camera the 2,8/3.5 C,'s, D's & E's are worth looking for. Cosmetic condition tends to paly a bug part in the selling price, but Ffordes seem to be a good place to buy them at fair prices, and you'd get a guarantee of a few months.
Ian