Hello Colin,
At the risk of generalising too much, where you will use it and the room illumination should be a big factor in your choice as you could go anything from a home theater projector (with typically better contrast and colour and lower maximum light intensity) to a venue/conference projector (which is typically much brighter at the expense of colour and contrast).
Is it used in a light controlled room/theatre? Would it be a permanent mount or portable? Projection distance and required image size? From my home theater days I can recommend Panasonic, JVC DLA projectors and some Epson units. I haven't checked recently, as I'm now happy with large TV, but I think you'll probably only easily find quality 4K units in the several thousand dollar range.
If your venue is home-theatre like in terms of light levels, then and older (1920x1080P) JVC DLA 350 /550 etc or possibly Panasonic would be an excellent 2nd hand choice (although check lamp usage life as for any projector). These days generic/copy replacement lamps are not too expensive $100-200, but in the past they were circa $800 OEM.
Even so maybe there are some
new 1920x1080P projectors which may be of worth. See some possibilities below and go and see them in vivo at
Klapp or
The Big Picture People. In conclusion .... So a large screen tv won't cut it at say 65 to 75 inch?
Some projectors in Melbourne....
https://klappav.com.au/collections/projectors
Best
JA