AP cluster without CMM

Hello, everybody.

We have one access point in our Canopy network and we are planning to deploy a second one.
The new AP would get data from the main AP. We need to make a deployment less expensive so we wouldn’t use a CMM for the first period.
There are two ways to transmit data between points –
via BHs
[CMM] -> [AP1] + [BHM] ------ [BHS] -> [AP2],
or by using just one SM at the second point (Remote Access Point in Motorola terms)
[CMM] -> [AP1] ------ [SM] -> [AP2]

So we have questions:
1. How many AP modules can be connected to BHS or SM? (I heard something about Y-cable to pass sync between modules)
2. Is it possible to use the same band frequencies no both sites (with 20/40 MHz gap) in case of Remote Access Point, not cross-band as Motorola recommends.

Is it true that an ordinary network switch can be used instead of CMM?

How to pass sync signal from one canopy module to several other modules? Y-cable - how to make it?

Using of two nearby frequencies in a remote AP - would it work?