In the end we took the balsa to Porta Velho and drive round to Ecuador, just arrived last week.

We spent many days in Manaus talking to the shipping companies and boat owners to get us to Peru. Why we did not take the river to Peru was because it seemed you could get held up at a port up river for a long time if a balsa was not going your way with available space. Its a risk, but if you have time on your side... Toby's info was very good, in theory its all possible, we wimped out.

I can say your Landrover opens up more options as our truck could not fit on all boats, only the cargo balsa's - there are smaller passenger boats that also can take smaller cars.

We bumped into difficulty with staying with our vehicle. Some balsa's were very insistent that we could not accompany our truck, would have to take a passenger ferry. May restrict your options if you wish to eat/sleep in your car, which we wanted to do. Always ask first!

Costs, you better be very good at negotiations or it will be expensive I suspect. Prices are all over the place. I imagine your trip will cost about $1.5k.

I believe your suggested route is the route, the only possible. We did hear that there were boats going direct to Iquitos from Manaus, so the same the other way, but then this was not consistently confirmed. As Toby says, really, there are no reservation or fixed anything. Even in Manaus its first come first served and that could change in a moment.

We don't speak Portuguese and it is necessary for this sort of journey. It can be complicated conversations so I hope you speak Spanish, you need to be very clear on everything.

Finally, make sure its raining or has been recently as if it ain't raining then the river don't run, well enough not to get stuck on a sand bank.

Good luck.