If you’re after something a little more rural than central Aber the Glynwern guest house in Llanilar has a self-catering house attached that I think sleeps 8.
Doesn’t seem to appear on the internet that much so you might have to phone to get the full details
Glynwern Guest House, Llanilar
Aberystwyth
Ceredigion
SY23 4NY
Tel: 01974 241203
Beautiful location right on the river Ystwyth with some big hills all around (see photo below from the weekend)
Don’t know the prices but I doubt it’s expensive
Has some garages
About 20-30 mins walk to the local pub
5/6 miles from Aber
Run by a very friendly but slightly potty lady
Good sewin (sea trout) fishing in the river, which is also perfect for stone skimming
Disclaimer. I’ve not stayed there but know the area very well and have known the owner my entire life (she’s always been potty) so the place may be an absolute dive. I spoke to some people who were staying there last week and they didn’t volunteer that it’s awful but I didn’t ask either. They have been going for the last few years though so they must be vaguely happy with it.