Honestly, it's most important that the oil is good quality and gets absorbed by the hair, instead of just leaving it oily. I think most hair oils that are not the cheapest available ones are probably fine, you could do some research online for your local market.

I have these gummi spiral/helix hairties. I guess it distributes the force better.

Hairdresser is also a once every six months affair for me. To like cut the tips and stuff.