What device with powerful WIFI, RJ45 and 30$ - 50$?

Hello,

I just want to know your recommendation about this.
I am looking for a device with these requirements:

WIFI with the possibility to attach an antenna and use 2 SSIDs.
RJ45
SD Card reader.
Price no more than 30$ - 50$, but a bit more would be also considered.
LEDE support (of course)

The use case is this: attach the device to a fast internet connection using the cable and share internet with several close neighbours. One SSID for a captive portal and another one is a private network encrypted. Should support SD Card because a lot of statistics would be written in a SQL database, so only flash is discarded. It should have an antenna connector, to use an outdoor antenna. Just that.

I already tried Raspberry Pi Zero, RPI 3 and Orange Pi. None of them support more than one SSID (which is annoying, most wifi adapters do it). Moreover, raspberries don't have an antenna connector, and adding that manually could bring legal problems (because regulations invalidation).
I also tried a Mikrotik router and it is really powerful (WIFI), but it only has flash memory.
Perhaps using a USB dongle could be another possibility.

Thanks a lot for your ideas.

how about this one:
http://www.gl-inet.com/mt300a/

Seems really interesting. Do you know if it supports more than one SSID? (otherwise don't worry, I will contact them)
Thanks a lot.

You are searching for a relatively cheap device: What's your favourite cheap LEDE/OpenWrt device?

SD card is narrowing down the search a lot. Supported devices with SD/µSD (29 devices in total):

Thanks! That's really useful. I check that right now.
The SD Card requirement is just because I need to write often. As far as I know, it is not a good idea to do that in a flash memory. Perhaps, apart from the SD Card, there is another way.

also you could use an usb drive

this - I've got a tiny USB 16GB flash drive connected for logs, and a larger 320GB SATA2 drive (pulled from a 2011 Macbook Pro that was upgraded to an SSD) in an enclosure for file storage.