If I were to order an ADA1000 Amplifier with 7 channels, how many single-ended RCA inputs would I get?

The reason I’m asking is that I’m looking at buying a new AVR for Christmas. I currently have a 5 year old Denon AVR-4520CI in the home theatre powering a 7.1 set-up consisting of M60’s, VP160, QS8’s and M2’s. There’s also an EP-500. I want to move the Denon upstairs to the TV and replace a 10 year old AVR-3808CI. Now, I’ve been eyeing a Marantz SR8012 which runs $3999, but someone mentioned going with separates due to the fact that the amp won’t need to be replaced every time the AVR does due to the ever-changing features. After doing some research, I found that going with a 7 channel ADA1000 and a Marantz SR5013 would save me $600, but still give me all the latest features I want. The thing I can’t wrap my head around is the pre-outs. The SR5013 has only a single pair of RCA outs for the fronts, a single one for the centre, and another single pair for the surrounds and surround backs. That means I’d need a total of 7 RCA inputs on the amp, so how does that work when it comes to choosing how many channels I’d want the amp to have in order to power all 7 channels of the AVR?

Ordering an ADA-1000-7 would get you 7 inputs.

One could argue that you only really need an ADA-1000-4.
3 for L/R/C channels and the fourth just in case you decide to run fronts requiring 2 channels per speaker in the future.
I've gone this route and let my AVR handle the 4 surround speakers.
Long term I plan on adding an ADA-1500-4 to my gear stand/rack and the 1000 will be dedicated for surround duty.
This assumes the AVR you're considering has an amplifier built in.

One more thought...make sure the AVR you get allows for seperate crossover settings for each speaker. A universal crossover setting will limit you if you don't want to tax your surrounds while using a lower cross over for your L/R/C channels.

Thanks for the advice!