...My personal recommendation is to see what a Canon T4 or T5i with a Tamron 18-270mm lens will run...
A one-lens-does-it-all solution is usually a big mistake. It means you are always stuck with an extra large, extra long lens with too small an aperture for many purposes.
Stick with major brands. And look for zoom lenses with an approximately 3:1 zoom ratio, certainly not 15:1.