With an FBC tuner (available on GB UE 4K, GB UHD 4k, Vu Solo 4K, Vu Uno 4K, Vu Duo 4K, Vu Ultimo 4K), the 8 satellite demodulators will allow you to record a lot more than 4 channels using a normal LNB. Add a unicable 2 LNB, you shouldn't get any problems up to 30 channels.
The GigaBlue to which links were posted are the cheapest, best you buy with a PNP Terrestrial tuner as USB tuners don't work.
The only FBC receiver that takes a 3.5 drive is the Ultimo4k
Best you ring the retailer and talk before buying to avoid misunderstanding.