Take a look at the mongooses and schwinns. Preferably over $250 so you dont have to swap out as many parts. I bought a $332 schwinn protocol 2.7 full sus and took it, stock, on a fast flowy trail, and the biggest things you will need with that bike (for a $1200 750w ebike build mind you, there isn't enough space in the frame for an engine) are the $135 suntour xcr air sprung fork, $97 fidgetgear 150mm e2e rear shock, and preferably a $45 SRAM x4 derailleur if you want it quiet and smooth. The stock rims are double walled beasts, and I haven't warped them yet despite several hard trail crashes. You may want to swap the tires out for something a bit more xc than what they currently have on there, wont run you more than $60 for a pair of continentals. Go ahead and slap on a $10 short stem for more control. If you turn it into an ebike, feel free to pull of that front derailleur. You won't need it anymore. Also, pull off those combo levers and swap those out for a <$25 SRAM X4 standalone rear shifter and a $150 avid hydraulic brakeset with dot5 fluid. If you plan on going freeway speeds, definitely get $30 adapters for 180mm to 203mm disc brakes. All this will give you a trail worthy bike that can handle high speeds with maximum control and a clean cockpit. You could even slap on a $30 1200lm headlight, with another $15 for a decent brake light. Add a flashy blue fender set to mount the light to, and keep you, the bike, and the motor clean for another $41. The gloss fenders will add a nice contrast to the matte frame. Everything mentioned here is available on amazon. If that two stroke engine is the one you are using, the $350 Schwinn Bonafied should have you covered.
Disclaimer: I am not advertising any product on behalf of the sellers or manufacturers. I have not been compensated in any way by anybody. The parts recommendations are strictly personal preference while the prices reflect my own choices in parts. The prices given may change at any time without warning, and should only be used as a guide for finding the budget required to acquire all parts. Under no circumstance shall I be held responsible for financial losses due to decisions made after reading this post.
That last one was just to cover my bases, nothing against you guys.